• Wind and Structures
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• v.4 no.4
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• pp.279-298
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• 2001

The greatest suction on the cladding of flat roof low-rise buildings is known to occur beneath the conical vortices that form along the roof edges for cornering winds. In a companion paper, a model of the vortex flow mechanism has been developed which can be used to connect the surface pressure beneath the vortex to adjacent flow conditions. The flow model is experimentally validated in this paper using simultaneous velocity and surface pressure measurement on a 1 : 50 model of the Texas Tech University experimental building in a wind tunnel simulated atmospheric boundary layer. Flow visualization gives further insight into the nature of peak suction events. The flow model is shown to account for the increase in suction towards the roof corner as well as the presence of the highest suction at wind angles of $60^{\circ}$. It includes a parameter describing vortex suction strength, which is shown to be related to the nature of the reattachment, and also suggests how different components of upstream turbulence could influence the surface pressure.

• Journal of Wetlands Research
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• v.19 no.3
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• pp.287-295
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• 2017

In this study, rainfall runoff characteristics according to peak concentration were analyzed using the water quality and flow data in the Geumho river, and the direction of nonpoint source management such as monitoring and management period by pollution source was derived. Peak Water Quality Concentration is the concept that utilizes the extreme value as the concentration of non-point pollution control standard with the highest water quality in the rainwater runoff. Using this method, the evaluation factors such as cumulative precipitation(total precipitation), peak water quality concentration, cumulative precipitation up to peak water quality concentration, time to peak water quality concentration, and EMC to peak water quality concentration were examined and long- Rainfall runoff characteristics of nonpoint sources were analyzed. The results of the analysis suggested proper monitoring and management method to manage nonpoint source.

• Journal of the Korean Association of Geographic Information Studies
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• v.2 no.2
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• pp.45-58
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• 1999

Digital map is utilized for an effective display of the distributions of the hydrogeological variables such as water table height(hydraulic head) and log-transmissivity(lnT) in north Pohang, KyungBug. Specifically the geostatistical method kriging is used to construct the distributions in an unconfined aquifer from a finite set of measured data. The experimental variograms for both the head and lnT suggest spherical models with nugget of 0 and range of 6km. The kriged results by using these variograms show that the head decreases primarily from the west to the east with a large peak in the north-western part and lnT is at the maximum level in the central part with outwardly decreasing trend. The constructed delineation is also used to calculate the flow field in the region. Finite differences with second order consistency are used to calculate the fluxes in the east(x) and north(y) across a vertical cross-section of unit width and height equal to the thickness of the wet zone in the aquifer. It is demonstrated that the flow is dominantly in the east with diverging trend on the eastern hillside of the water table peak. A few convergent spots also appear.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.4
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• pp.399-406
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• 2014

PURPOSE: The purpose of this study was to examine the effects of respiratory muscle training on respiratory function, respiratory muscle strength, and cough capacity in stroke patients. METHODS: This study used a nonequivalent control group pre-post test design. We recruited thirty-four stroke patients(16male, 18female), who were assigned to intervention (n=17), or control (n=17) groups. Both groups participated in a conventional stroke rehabilitation program, with the intervention groups also receiving respiratory muscle training 20 minutes a day, three times a week, for 4 weeks. Respiratory function (forced vital capacity) and respiratory muscle strength (maximal inspiratory pressure, maximal expiratory pressure) were assessed by spirometry. Cough capacity (peak expiratory flow) was assessed using a peak flow meter. The collected data were analyzed by independent and paired t-tests. RESULTS: The intervention group showed a significant increase in the forced vital capacity (FVC), maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP) and peak expiratory flow (PEF) at the end of the program, while the control group showed no significant changes. CONCLUSION: This study showed that respiratory muscle training increased respiratory function, respiratory muscle strength, and cough capacity in stroke patients and prevented a decrease in cough capacity. These findings suggest that respiratory muscle training effect on respiratory function, respiratory muscle strength and cough capacity for rehabilitation in patients with stroke.

• The Korean Journal of Rehabilitation Nursing
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• v.10 no.2
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• pp.108-115
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• 2007

Purpose: This study was to investigate the effects of respiratory rehabilitation training on the respiratory functions of hospitalized cervical spinal cord injury patients. Methods: One group pre and post test design was used. Subjects were 20 cervical spinal cord injury inpatients of the national rehabilitation center. Training program consisted of air cumulation training, manual assisted coughing training, and abdominal breathing. Trained rehabilitation nurse implemented 20 minutes program twice a day for 4 weeks. Respiratory function was measured as peak coughing flow rate, and perceived respiratory difficulty after activity on wheel chair for 30 minutes and during speaking and singing. Perceived respiratory difficulty was measured with modified Borg scale. Also content analysis was done with the result of open ended question about subjective feeling about training. All variables were measured 3 times before, 2weeks and 4 weeks after the program. Results: Peak coughing flow rate significantly improved after compared to before training. Also all three perceived respiratory difficulty variables decreased significantly after training. In the content analysis, 'it's easier to cough up phlegm' was the most frequent answered subjective feeling. 'Sound at speaking and coughing became louder', 'respiratory volume increased', and 'comfortable chest feeling' were frequent answered subjective feeling, in order. Conclusion: Although it is preliminary since no control group, respiratory rehabilitation training was found to be effective to improve respiratory function in terms of peak coughing flow rate, perceived respiratory difficulty, and subjective feeling. It is necessary further systemic research to investigate the effects of respiratory rehabilitation training.

• Physical Therapy Korea
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• v.16 no.1
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• pp.10-17
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• 2009

The aim of this study was to investigate the effect of abdominal drawing-in maneuver (ADIM) on peak exploratory flow (PEF), forced exploratory volume in 1 second ($FEV_1$), and low back pain during forced expiration. Twenty-two subjects (14 subjects in experimental group, 8 subjects in control group) participated in this study. The stabilizer was used for ADIM training for five consecutive days. Vitalograph PEF/$FEV_1$ DIARY and visual analogue scale (VAS) were used to determine forced expiratory pulmonary function and low back pain, respectively. Independent t-test and analysis of covariance were used for statistical analysis with a significance level of .05. The findings of this study were as follows: 1) There were no significant differences of ADIM effect on PEF and $FEV_1$ between experimental group and control group. 2) There was a significant pain reduction in experimental group with ADIM. 3) PEF and $FEV_1$ increased significantly in the fifth day compared with the first day pre-exercise baseline. Therefore, it is concluded that ADIM was effective in improving PEF and $FEV_1$, and reducing VAS during forced expiration in patients with chronic low back pain.

• Water for future
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• v.29 no.3
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• pp.207-216
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• 1996

The subject research attempts to evaluate the variations of total runoff volume, peak flow, and travel time depending on the urbanhization, return periods and rainfall patterns under the situations that the preparation of a large residential site at the lowland areas of the downstream of Dongsu stream in Bupyung-Gu, Incheon city is progressed and the area will be eventually fully developed. The ILLUDAS model was used for the runoff analyses based on 3 differend steps of urbanization and 4 different types of Huff's quantile according to rainfall patterns is Huff's 4 quantile, Huff's 2 quantile, Huff's 3 quantile and Huff's 1 quantile. Under the 80 and 90 % of urbanization to the 70% of urbanization, the mean increasing ratio of total runoff volume for each case is 3.5 and 5.5 %, that of peak flow is 4.2 and 8.8%, and the mean decreasing ratio of travel time is 4.4 and 10.1%, respectively. The mean increasing ratio of total runoff volume according to the return periods is 3.0 and 5.4%, that of peak flow is 3.9 and 8.0% under the same conditions of urbanization.

• Annals of Rehabilitation Medicine
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• v.42 no.6
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• pp.798-803
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• 2018

Objective To investigate the relationship between peak cough flow (PCF), pulmonary function tests (PFT), and severity of dysphagia in patients with ischemic stroke. Methods This study included patients diagnosed with ischemic stroke, who underwent videofluoroscopic swallowing study (VFSS), PCF and PFT from March 2016 to February 2017. The dysphagia severity was assessed using the videofluoroscopic dysphagia scale (VDS). Correlation analysis of VDS, PFT and PCF was performed. Patients were divided into three groups based on VDS score. One-way ANOVA of VDS was performed to analyze PCF, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and age among the different groups. Results The correlation coefficients of VDS and PCF, VDS and FVC, and VDS and FEV1 were -0.836, -0.508, and -0.430, respectively, all of which were statistically significant at the level of p<0.001. The one-way ANOVA indicated statistically significant differences in PCF, FVC, FEV1, and age among the VDS groups. Statistically significant differences in VDS and age were observed between aspiration pneumoia and non-aspiration pneumonia groups. Conclusion Coughing is a useful factor in evaluating the risk of aspiration in dysphagia patients. Evaluation of respiratory and coughing function should be conducted during the swallowing assessment of patients with ischemic stroke.

• Safety and Health at Work
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• v.10 no.1
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• pp.47-53
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• 2019

Background: Despite growing concern over occupational exposure to particulate matter (PM) such as grain dust and diesel exhaust, information about the exposure level and health implications among workers in small-scale milling enterprises in developing countries like Nigeria has not been adequately documented. The purpose of this study was to assess the level of exposure to grain dust and diesel exhaust and effect on lung function among grain millers in food markets in Ibadan metropolis, Nigeria. Methods: The study adopted descriptive cross-sectional design with a comparative approach. Sixteen grain milling shops each were randomly selected from two major food markets in Ibadan metropolis for indoor $PM_{10}$ and $PM_{2.5}$ monitoring. Seventy-two respondents each were proportionately selected from grain millers and shop owners for forced expiratory volume in one second and peak expiratory flow rate tests. Results: The $PM_{2.5}$ concentrations for both market locations ranged between 1,269.3 and $651.7{\mu}g/m^3$, while $PM_{10}$ concentrations were between 1,048.2 and $818.1{\mu}g/m^3$. The recorded concentrations exceeded the World Health Organization guideline limit of $50{\mu}g/m^3$ and $25{\mu}g/m^3$ for $PM_{2.5}$ and $PM_{10}$, respectively. As compared with control group (2.1 L), significantly lower forced expiratory volume in one second value (1.61 L) was observed among the exposed group (p < 0.05). Likewise, significantly lower peak expiratory flow rate value (186.7 L/min) was recorded among the exposed group than the control group (269.51 L/min) (p < 0.05). Conclusion: Exposure to grain dust and diesel exhaust accentuated respiratory disorders with declines in lung functions amongst grain millers. Improved milling practices and engaging cleaner milling facilities should be adopted to minimize exposure and related hazards.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.1
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• pp.23-31
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• 2021

Purpose : To compare the immediate effects of air stacking maneuver using resuscitator bags and balloons. Methods : Twenty healthy young adults participated in this study. Forced vital capacity (FVC) and peak cough flow (PCF) tests were performed at pre-intervention, and then, the maximum insufflation capacity (MIC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, peak expiratory flow (PEF), and peak cough flow (PCF) were measured using the air stacking maneuver via resuscitator bags and balloons. Interventions were randomly performed, and a 40-min break was provided between interventions. The evaluation process in this study was conducted in accordance with the guidelines of the American Thoracic Society (ATS) 2019. To compare the three outcomes measured at pre-and post-interventions, repeated measures analysis of variance was performed. Results : A significant difference was found in the MIC, FEV1, PEF, and PCF after the air stacking maneuver using resuscitator bags and balloons, whereas no significant difference was observed between resuscitator bags and balloons. Conclusion : No significant difference was found in the immediate effect of the air stacking maneuver using resuscitator bags and balloons in this study. Air stacking maneuver using balloons can increase the success rate of the techniques by providing visual feedback on the amount of air insufflation when performed with balloon blowing exercise. Balloons are cheaper and easier to buy compared to manual resuscitator bags; therefore, education on the air stacking maneuver using balloons will have a positive effect on pulmonary rehabilitation.