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By enhancing vagal activity, auricle transcutaneous electric nerve stimulation (TENS) is developed as a non-invasive therapy for heart failure. Nevertheless, though shoulder TENS used for treating adhesive capsulitis could affect vagal tone, its potential impact on heart functions remains unclear. In this study, electrocardiogram (ECG) and heart rate (HR) of subjects in response to sham, right-sided, or left-sided shoulder TENS (TENS-S, TENS-R, and TENS-L, respectively; 5 min) were recorded and analyzed. During the stimulation period, TENS-R constantly and TENS-L transiently decreased the HR of subjects; both TENS-R and TENS-L increased powers of the low- and high-frequency spectra. While TENS-R exhibiting no effect, TENS-L increased the ratio of low/high-frequency power spectrum indicating TENS-R decreased the HR through potentiating cardiac vagal tone. Collectively, these results suggest TENS could be an early and non-invasive therapy for heart failure patients before considering implant devices or devices are not feasible; moreover, therapists/physicians need to carefully monitor the potential adverse events during treatment for patient safety.Trial registration: The study protocol was registered in ClinicalTrials.gov (NCT03982472; 11/06/2019).

Building cooling energy use is regarded as the hot topic of building research due to its increasing trend at a rate proportional to the total direct energy use in urban areas nowadays. Urban greening as an effective countermeasure in reducing building cooling load has been attracting close attention although there is a shortage of quantitative measures for applying the general idea to a specific site or building. This study addresses this problem. The cooling effect of trees around buildings and the influence of tree characteristics on building cooling load reduction was quantified using microclimate field measurements and sap flow rate of trees. By integrating approaches of field measurements of microclimate and tree characteristics into EnergyPlus simulation of building energy use, the cooling effects of trees due to both shading and transpiration on buildings were quantified and discussed. Four scenarios were developed based on different tree characteristics for quantifying the influence of trees on saving of building energy use: Scenario 1 with treeless condition, Scenario 2 with existing trees condition in a case of Nanjing City, Scenario 3 with more tree shading condition, and Scenario 4 with more tree transpiration condition. The simulation results showed that compared to Scenario 1, Scenario 2 can reduce building energy use by 10.3% due to the benefits from existing trees shading and transpiration. More shading in Scenario 3 and a higher transpiration rate in Scenario 4 can reduce building energy use by 15.2% and 12.4%, respectively in comparison to that in Scenario 1.

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 Ta...

Urban areas encounter a common problem called the heat island effect. Public-space plantings and parks have become a crucial countermeasure for decreasing urban temperatures. In this study, field measurements were carried out in a subtropical park in the summer to investigate the effect of plantings on microclimate and the thermal environment of pedestrian areas. It was found that obstructions affected the wind field; although cold air enters parks, an overcrowding of plants resulted in temperature rises in downstream areas. Shading is a key to thermal comfort in both tropical and subtropical regions, and its effect is augmented by ventilation. Trees that are planted without proper planning can decrease wind movement, which in turn has a detrimental effect on thermal comfort, especially downwind. Wind corridors through urban parks can promote both shading and ventilation, improving thermal comfort, and should thus be considered when designing the layout and trimming of plantings. Data from both fixed- and mobile-type measurements were used to validate the feasibility of a computational fluid dynamics simulation model. It was observed that wind speed and shading are the two main variables that influence the human comfort index, based on which a simpler human comfort assessment was proposed to replace the conventional index, standard effective temperature (SET*). The proposed method can be used as a guideline for landscape architects when designing planting locations.

The exhaust performance of a cooling tower placed in the interior space of a building is crucial due to limited space and stochastic ambient wind conditions. Improper design of the cooling tower could lead to a reduction in thermal efficiency and could also deteriorate the operational performance of the chillers. In this paper, the exhaust performance of cooling towers in a super high-rise building considering both side exhaust and interlayer exhaust methods is investigated using CFD simulations. The results show that the exhaust performance of cooling towers under interlayer exhaust is better than that under side exhaust. However, the exhaust recirculation phenomenon of the cooling towers on the windward side caused by outdoor wind is still obvious because the outdoor wind speed is low. The total pressure differences between the inlet and outlet of the tower units under interlay exhaust become larger with increases in wind speed in each district. The fan total head should be carefully determined to overcome the surplus pressure drop caused by the wind. This study helps to guide other similar cases utilizing the interior space of buildings for the cooling towers.

Academic studies concerning how climate influences Asian heritage are rare. The object of this study was to utilize the concept of heritage climatology together with a spatial analysis approach that includes respective climate parameter risks to cultural heritage sites. The study area, Tainan City, Taiwan, is in a subtropical zone south of the Tropic of Cancer. Tainan has nearly 300 hundred years of rich history and a multicultural background. This study used maps to gain information about potential climactic threats to Tainan's cultural-historical legacy. There are four kinds of map that use ArcGIS to analyse and demarcate regions not only by climate parameters but also by risk to heritage. These four types of map are climate maps, heritage climate maps, heritage maps and heritage risk maps. Climate maps give the short- to medium-term general status of the climate in Tainan City and thus served as the foundation of the other maps used in this study. Heritage climate maps give data concerning index factors that influence wood and stone materials. Heritage maps show locations of cultural heritage sites on an administrative map and categorize them according to their historic value. Heritage risk maps use accumulated calculations to superimpose the heritage climate map onto the heritage map in order to evaluate the risks to heritage sites in certain areas and categorize the levels of risk. Heritage sites in mountainous areas generally need to be protected from heavy rain, whereas downtown city environments, due to the urban heat island effect, require better protection against heat and cracking. By comparison of our field study results and climate risk maps, we found that in urban areas wooden materials have a higher risk of structural cracking, colour fading and bio-degradation, while coastal areas have a higher risk of weathering of stone materials.

This study analyzes the PV potential on rooftops and vertical facades in the research area of West Central District of Tainan City, a rich insolation area in Taiwan. By using the energy calculating software EnergyPlus and the grid-based computational fluid dynamics (CFD) software Windperfect, the electrical energy generated by PV modules on vertical walls from eight directions in both shading-covered areas and non-shading-covered areas was simulated and calculated. Three databases – the database of the electrical energy generated by building facades, of spatial information, and of shadow coverage – are established to estimate the potential electrical energy. The covered-shading condition was simulated by sunshine trajectory method, and the insolation potential of building surface was evaluated by analyzing the accumulating insolation hours and the spatial location data. It was observed that shading affects vertical facades more significantly. The average electricity generation of per unit area on rooftops demonstrates that the electrical energy in summer is twice as much as that in winter. Although the electrical energy generated by that of per unit area on vertical facades is higher in winter, it is only 1.1 times greater than that in summer. If the amount of electrical energy generated is taken into consideration, the installation area for the southwest walls should be 1.5 times larger than that of the rooftops so that the same amount of electrical energy can be generated. When considering the installation of PV panels in the research area of this study and other geographically similar locations, the priority should be the rooftops, followed by southeast-, southwest-, and south-facing vertical facades.

The purpose of the study was to evaluate potential locations for the installation of small wind turbines in urban areas. Four study sites in An-Ping, Tainan were chosen for measurement in this empirical study. The measurement data were used to verify the computational fluid dynamics (CFD) model. The weather information was gathered in order to understand the overall wind environment in the studied area. CFD software was used to simulate the wind environment in the study area from 16 directions. The distribution of wind environment was first presented, and then the distribution of exceedance probability in each grid, which was based on an exceedance probability assessment, was obtained. In addition to the installation heights of the turbines, the influence of surrounding buildings was taken into consideration. Finally, a wind energy potential map indicating the potential regions and non-potential regions for installing small wind turbines was illustrated by the ArcGIS system. A wind energy potential map, superimposed with locations of buildings of different floor heights, was used to evaluate the possible sites for the installment of small wind turbines at heights of 10, 20, and 30 m. The results proved that installing micro wind turbines in open spaces and on the roofs of three-, four-, and five-story buildings at a height of 20 m is relatively beneficial for coastal urban areas.

Recently, because of the growing importance of issues such as global warming and the heat island effect, maintenance of trees and the design of planting on green land have become increasingly significant. This article focuses on variation in sap flow in, and transpiration of, Araucaria heterophylla in Tainan Park. In order to understand the relationship between the allocation of plantings and the physiological functions of trees, the influence of cover conditions and meteorological conditions related to insolation were taken into consideration. First, under the same allocating conditions, the amount of transpiration was affected by differences on the ground (grassy and sandy). The differences in cover conditions have a lot to do with the water physiology of the tree. In addition, other factors such as insolation and changes in the speed of sap flow during a day are positively correlated. The results of this study are the main factors for evaluating the allocation and density of tree plantings and also for analysing the relationship between microclimatic environments and the physiological characteristics of trees. [Formula: see text]

The present study explains the application of a numerical simulation to investigate the thermal environment of a new riverside residential development in summer. The case study area consists of more than one hundred two-story detached houses built next to a river near Tokyo, Japan. According to the meteorological data, prevailing wind directions are at an angle to the northbound river flow affecting the microclimate of the study area in terms of surface temperature of land and buildings, air temperature and wind distribution at pedestrian height. These factors have been estimated using the stepwise CFD (computational fluid dynamics) simulation of radiation, conduction and convection. This method leads to an improvement of outdoor thermal environment by manipulating the site design and layout planning scenarios. The effect of river, permeable pavements and green space on thermal environment is examined by the site design options. Likewise, the impact of building arrangement is evaluated using alternative layout planning scenarios. In total, five scenarios have been simulated for the proposed sustainable development as explained in the paper. Above simulations provided an insight into the mitigation effects of each countermeasure. It is also shown that the management of inflow paths and the creation of wind paths for the interior of the site have the potentials to improve the outdoor thermal environment of riverside residential development.

Taipei City, located in the subtropical zone, has a basin landform. The summer is always hot and humid and the air temperature right after sunset is typically higher than 30 °C. Heat rejection from residential buildings in urban area, equipped with lots of the window type air conditioners, not only increases the air temperature outside, but also burdens the cooling load. Based on the time schedule of air conditioner use of Taipei citizens, the heat rejection/building energy use and the air temperature distribution were evaluated, and finally the additional electric consumption of air conditioners was predicted. Two software, EnergyPlus (building energy program) and Windperfect (CFD, computational fluid dynamics software) were employed in this study. In the CFD simulation, the geometry of buildings that covers 700 m in diameter was created with GIS (geographical information system) and the total mesh number was more than 3 millions. Three specified temperatures (Tam, Tbu and Tac) were used to describe the temperature distribution within the urban canopy by hourly time variation and spatial distribution with height and horizontal profile. The results revealed that the temperature gradually increased with height and the temperature next to the buildings was always higher than the ambient air. The feedback (penalty) of heat rejection to cooling load was found 10.7% during 19:01 to 02:00 h on the following day.

The main work in the research focuses on the analysis and mitigation of the anthropogenic heat discharged from buildings, which is one of the main reasons leading to the heat island effect. The residential and commercial buildings, divided into 10 categories, with HVAC systems were analyzed by the building energy program, EnergyPlus. With the help of GIS, the heat rejection of all the residential and commercial buildings in DaAn Ward of Taipei City were evaluated, in which the spatial data and diurnal variation of the heat rejection were described by 3-h time periods. Furthermore, the effect of mitigation strategies was discussed. The first strategy was to change the wall/roof material of building envelope. The second and third strategies, from the viewpoint of energy saving, were to change the temperature setting of air conditioners and to turn off the lighting and equipment when not in use. The fourth strategy was to use a better efficiency of the cooling systems. Finally, the evaluation of installing the water-cooled cooling system, which discharges heat in the form of sensible and latent heat, was also included.

Japan's Air Pollution Control Law signed in 1968 prescribes the maximum permissible limits of motor vehicle exhausts as well as establishing mechanisms for monitoring air pollution In this paper, the grey relational grade of air pollutants from ambient air pollution and roadside air pollution monitoring stations is used to look at the relationship between air pollution and transportation. The results indicated that the ambient and roadside air quality increased by rose from 1975 to 2004 but less fast than the growth in traffic. Some of this may be attributable to the legislation but there have also been other measures since 1968 that have also contributed.

In this paper, we present the microwave-assisted synthesis and characterization of alkaline nanomaterials for the preservation of cultural heritage. Calcium and barium hydroxide nanomaterials suspended in aqueous as well as alcoholic medium were applied on different samples to check their effectiveness. The effect of treatment was measured using pH value and alkaline reserve test. The alkaline reserve test results indicate improvement in the alkaline buffer with significant reduction in acidity of the papers and improvement in pH value of the surfaces. Ethanol was found as best solvent on the basis of suspension of nanoparticles, pH value and ease of application through spray gun. Accelerated ageing test revealed that the reinforcement effect of these nanomaterials persisted throughout the ageing. All the results converged in individuating these nanometric particles as an innovative, completely compatible, and efficient material for the consolidation of old and new paper surfaces.

Heritage conservation studies concerning how climate influences Asian cultural heritage are rare. The object of this study was to utilize the concept of heritage climatology together with a spatial analysis approach that includes respective climate parameter risks to cultural heritage sites. The study area, the island of Taiwan, is located between the Ryukyu isles in the north and the Philippine archipelagos in the south. It lies across the Tropic of Cancer, and its climate is influenced by the East Asian Monsoon. Northern and central Taiwan has a humid subtropical climate while most of southern Taiwan has a tropical monsoon climate. With nearly 300 hundred years of history, Taiwan displays much cultural diversity, which is the result of racial mingling of indigenous peoples, Spanish, Dutch, Chinese, and Japanese since ancient times, leaving behind rich cultural heritage sites.

In order to alleviate the urban HI (Heat Island) effect, green belt planning has recently been considered one of the priorities in the urban environment greening. This study discusses the influence on microclimate which may be brought by boulevards consisting of different tree species and their allocations. Combining the results of Sap Flow Measurement with the analyses on dense and open canopy, four findings were concluded: (1)Street trees have a critical influence on easing urban HI effect. (2)The amount of tree transpiration in open canopy is larger than that of in dense canopy due to heated ground. (3)The variations of humidity in both dense and open canopy have little difference. (4)In order to lower the surrounding temperature, boulevards of dense canopy in cities appear to be more effective than that of open canopy. The results point out that allocation of street trees plays a critical role in cooling down the surrounding environment. Hence, improving urban roads’ environment through planning planting allocations is feasible and effective. In this study we have proposed several allocation designs of street trees that could serve as a reference for planning the planting of urban street trees.

This study examines the blocks around the main station of the Kaohsiung Railway Underground Project in which the 400 m around station will be redeveloped. Two concepts, sustainable urban design and TOD (transit oriented development), were integrated to develop a new planning approach called the original Green-TOD. Among the key issues of Green-TOD, the relation between pedestrian space design and air ventilation is a crucial issue for providing pedestrians with amenities in a tropical climate like Kaohsiung. In this study, wind speed and wind direction, which were selected from the two main high traffic periods during the summer, served as the primary simulation settings of computational fluid dynamics (CFD), and wind distribution between roadside-based and street-block-based developments were compared. Major implemented policies for urban design, including the incentives for floor area ratio (FAR), building mass and layout, and open space design measures, are explicitly addressed as well. The results of the CFD simulation show the quality of the ventilation can be improved through land-use control measures.