• Title/Summary/Keyword: MWT

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Evaluation of long-term water quality management policy effect using nonparametric statistical methods

  • Jung, Kang Young;Ahn, Jung Min;Cho, Sohyun;Lee, Yeong Jae;Han, Kun Yeun;Shin, Dongseok;Kim, Kyunghyun
    • Membrane and Water Treatment
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    • v.10 no.5
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    • pp.339-352
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    • 2019
  • Long term water quality change was analyzed to evaluate the effect of the Total Maximum Daily Load (TMDL) policy. A trend analysis was performed for biochemical oxygen demand (BOD) and total phosphorus (TP) concentrations data monitored at the outlets of the total 41 TMDL unit watersheds of the Nakdong River in the Republic of Korea. Because water quality data do not usually follow a normal distribution, a nonparametric statistical trend analysis method was used. The monthly mean values of BOD and TP for the period between 2004 and 2015 were analyzed by the seasonal Mann-Kendall test and the locally weighted scatterplot smoother (LOWESS). The TMDL policy effect on the water quality change of each unit watershed was analyzed together with the results of the trend analysis. From the seasonal Mann-Kendall test results, it was found that for BOD, 7.8 % of the 41 points showed downward trends, 26.8 % and the rest 65.9% showed upward and no trends. For TP, 51.2% showed no trends and the rest 48.8% showed downward trends. From the LOWESS analysis results, TP began to decrease in most of the unit watersheds from mid-2010s when intensive chemical treatment processes were introduced to existing wastewater treatment plants. Overall, for BOD, relatively more points were improved in the main stream compared to the points of the tributaries although overall trends were mostly no trend or upward. For TP, about half of the points were improved and the rest showed no trends.

Intra-event variability of bacterial composition in stormwater runoff from mixed land use and land cover catchment

  • Paule-Mercado, Ma. Cristina A.;Salim, Imran;Lee, Bum-Yeon;Lee, Chang-Hee;Jahng, Deokjin
    • Membrane and Water Treatment
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    • v.10 no.1
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    • pp.29-38
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    • 2019
  • Microbial community and composition in stormwater runoff from mixed land use land cover (LULC) catchment with ongoing land development was diverse across the hydrological stage due different environmental parameters (hydrometeorological and physicochemical) and source of runoff. However, limited studies have been made for bacterial composition in this catchment. Therefore, this study aims to: (1) quantify the concentration of fecal indicator bacteria (FIB), stormwater quality and bacterial composition and structure according to hydrological stage; and (2) determine their correlation to environmental parameters. The 454 pyrosequencing was used to determine the bacterial community and composition; while Pearson's correlation was used to determine the correlation among parameters-FIB, stormwater quality, bacterial composition and structure-to environmental parameters. Results demonstrated that the initial and peak runoff has the highest concentration of FIB, stormwater quality and bacterial composition and structure. Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes were dominant bacteria identified in this catchment. Furthermore, the 20 most abundant genera were correlated with runoff duration, average rainfall intensity, runoff volume, runoff flow, temperature, pH, organic matter, nutrients, TSS and turbidity. An increase of FIB and stormwater quality concentration, diversity and richness of bacterial composition and structure in this study was possibly due to leakage from septic tanks, cesspools and latrines; feces of domestic and wild animals; and runoff from forest, destroyed septic system in land development site and urban LULC. Overall, this study will provide an evidence of hydrological stage impacts on the runoff microbiome environment and public health perspective.

Trend analysis of rainfall characteristics and its impact on stormwater runoff quality from urban and agricultural catchment

  • Salim, Imran;Paule-Mercado, Ma. Cristina;Sajjad, Raja Umer;Memon, Sheeraz Ahmed;Lee, Bum-Yeon;Sukhbaatar, Chinzorig;Lee, Chang-Hee
    • Membrane and Water Treatment
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    • v.10 no.1
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    • pp.45-55
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    • 2019
  • Climate change has significantly affected the rainfall characteristics which can influence the pollutant build-up and wash-off patterns from the catchment. Therefore, this study explored the influence of varying rainfall characteristics on urban and agricultural runoff pollutant export using statistical approaches. For this purpose, Mann-Kendall and Pettitt's test were applied to detect the trend and breakpoint in rainfall characteristics time series. In addition, double mass curve and correlation analysis were used to drive the relationship between rainfall-runoff and pollutant exports from both catchments. The results indicate a significant decreased in total rainfall and average rainfall intensity, while a significant increased trend for antecedents dry days and total storm duration over the study periods. The breakpoint was determined to be 2013 which shows remarkable trend shifts for total rainfall, average rainfall intensity and antecedents dry days except total duration. Double mass curve exhibited a straight line with significant rainfall-runoff relationship indicates a climate change effect on both sites. Overall, higher pollutant exports were observed at both sites during the baseline period as compared to change periods. In agricultural site, most of the pollutants exhibited significant (p< 0.05) association with total rainfall, average rainfall intensity and total storm duration. In contrast, pollutants from urban site significantly correlated with antecedent dry days and average rainfall intensity. Thus, total rainfall, average rainfall intensity and total duration were the significant factors for the agricultural catchment while, antecedents dry days and average rainfall intensity were key factors in build-up and wash-off from the urban catchment.

Future water quality analysis of the Anseongcheon River basin, Korea under climate change

  • Kim, Deokwhan;Kim, Jungwook;Joo, Hongjun;Han, Daegun;Kim, Hung Soo
    • Membrane and Water Treatment
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    • v.10 no.1
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    • pp.1-11
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    • 2019
  • The Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) predicted that recent extreme hydrological events would affect water quality and aggravate various forms of water pollution. To analyze changes in water quality due to future climate change, input data (precipitation, average temperature, relative humidity, average wind speed and sunlight) were established using the Representative Concentration Pathways (RCP) 8.5 climate change scenario suggested by the AR5 and calculated the future runoff for each target period (Reference:1989-2015; I: 2016-2040; II: 2041-2070; and III: 2071-2099) using the semi-distributed land use-based runoff processes (SLURP) model. Meteorological factors that affect water quality (precipitation, temperature and runoff) were inputted into the multiple linear regression analysis (MLRA) and artificial neural network (ANN) models to analyze water quality data, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), suspended solids (SS), total nitrogen (T-N) and total phosphorus (T-P). Future water quality prediction of the Anseongcheon River basin shows that DO at Gongdo station in the river will drop by 35% in autumn by the end of the $21^{st}$ century and that BOD, COD and SS will increase by 36%, 20% and 42%, respectively. Analysis revealed that the oxygen demand at Dongyeongyo station will decrease by 17% in summer and BOD, COD and SS will increase by 30%, 12% and 17%, respectively. This study suggests that there is a need to continuously monitor the water quality of the Anseongcheon River basin for long-term management. A more reliable prediction of future water quality will be achieved if various social scenarios and climate data are taken into consideration.

Analysis of pollutant build-up model applied to various urban landuse

  • Choi, Jiyeon;Na, Eunhye;Ryu, Jichul;Kim, Jinsun;Kim, Hongtae;Shin, Dongsuk
    • Membrane and Water Treatment
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    • v.10 no.1
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    • pp.13-17
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    • 2019
  • This study was conducted to analyse the application of pollutant build-up model on various urban landuses and to characterize pollutant build-up on urban areas as a source of stormwater runoff pollution. The monitored data from impervious surfaces in urban areas such as commercial (8 sites), industrial (10 sites), road (8 sites), residential (10 sites), recreational (5 sites) from 2008 to 2016 were used for the analysis of pollutant build-up model. Based on the results, the average runoff coefficients vary from 0.35 to 0.61. In all landuses except recreational landuse, the runoff coefficient is 0.5 or more, which is the highest in the commercial area. Commercial landuse where pollutants occur at the highest EMC in all landuse, and it is considered that NPS management is necessary compared with other landuses. The maximum build-up load for organic matter (BOD) was highest in the commercial area ($4.59g/m^2$), and for particular matter (TSS) in the road area ($5.90g/m^2$) while for nutrient (TN and TP) in the residential area ($0.40g/m^2$, $0.14g/m^2$). The rate constants ranged from 0.1 to 1.3 1/day depending on landuse and pollutant parameters, which means that pollutant accumulation occurs between 1 and 10 days during dry day. It is clear that these build-up curves can generally be classified based on landuse. Antecedent dry day (ADD) is a suitable and reasonable variable for developing pollutant build-up functions. The pollutant build-up curves for different landuse shows that these build-up curves can be generally categorized based on landuse.

Evaluation on the suspended solids and heavy metals removal mechanisms in bioretention systems

  • Geronimo, Franz Kevin F.;Maniquiz-Redillas, Marla C.;Hong, Jungsun;Kim, Lee-Hyung
    • Membrane and Water Treatment
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    • v.10 no.1
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    • pp.91-97
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    • 2019
  • Application of bioretention systems in Korea is highly considered due to its minimal space requirements, appropriateness as small landscape areas and good pollutant removal and peak hydraulic flow reduction efficiency. In this study, the efficiency of two lab-scale bioretention types having different physical properties, media configuration and planted with different shrubs and perennials was investigated in reducing heavy metal pollutants in stormwater runoff. Type A bioretention systems were planted with shrubs whereas type B were planted with perennials. Chrysanthemum zawadskii var. latilobum (A-CL) and Aquilegia flabellata var. pumila (A-AP) respectively were planted in each type A bioretention reactors while Rhododendron indicum linnaeus (B-RL) and Spiraea japonica (B-SJ), respectively were planted in each type B bioretention reactors. Results revealed that the four lab-scale bioretention reactors significantly reduced the influent total suspended load by about 89 to 94% (p<0.01). Type B-RL and B-SJ reactors reduced soluble Cr, Cu, Zn, and Pb by 28 to 45% that were 15 to 35% greater than the soluble metal reduction of type A-CL and A-AP reactors, respectively. Among the pollutants, total Cr attained the greatest discharged fraction of 0.52-0.81. Excluding the effect of soil media, total Pb attained the greatest retention fraction in the bioretention systems amounting to 0.15-0.34. Considering the least discharge fraction of heavy metal in the bioretention system, it was observed that the bioretention systems achieved effectual reduction in terms of total Cu, Zn and Pb. These findings were associated with the poor adsorption capacity of the soil used in each bioretention system. The results of this study may be used for estimating the maintenance requirements of bioretention systems.

Installation and operation of automatic nonpoint pollutant source measurement system for cost-effective monitoring

  • Jeon, Jechan;Choi, Hyeseon;Shin, Dongseok;Kim, Lee-hyung
    • Membrane and Water Treatment
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    • v.10 no.1
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    • pp.99-104
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    • 2019
  • In Korea, nonpoint pollutants have a significant effect on rivers' water quality, and they are discharged in very different ways depending on rainfall events. Therefore, preparing an optimal countermeasure against nonpoint pollutants requires much monitoring. The present study was conducted to help prepare a method for installing an automatic nonpoint pollutant measurement system for the cost-effective monitoring of the effect of nonpoint pollutants on rivers. In the present study, monitoring was performed at six sites of a river passing through an urban area with a basin area of $454.3km^2$. The results showed that monitoring could be performed for a relatively long time interval in the upstream and downstream regions, which are mainly comprised of forests, regardless of the rainfall amount. On the contrary, in the urban region, the monitoring had to be performed at a relatively short time interval each time when the rainfall intensity changed. This was because the flow rate was significantly dependent on the rainfall's intensity. The appropriate sites for installing an automatic measurement system were found to be a site before entering the urban region, a site after passing through the urban region, and the end of a river where the effects of nonpoint pollutant sources can be well-decided. The analysis also showed that the monitoring time should be longer for the rainfall events of a higher rainfall class and for the sites closer to the river end. This is because the rainfall runoff has a longer effect on the river. However, the effect of nonpoint pollutant sources was not significantly different between the upstream and the downstream in the cases of rainfall events over 100 mm.

Clinical Effectiveness of Acupuncture Related to Improvement in Quality of Life and Problems after Percutaneous Coronary Intervention : A Systematic Review (관상동맥 중재술 후 문제점 및 삶의 질 개선에 관한 침 치료 효과 : 체계적 문헌 고찰)

  • Lee, Ji Sung;Park, Ui Hyun;Kwon, Jung-nam
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.33 no.2
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    • pp.82-88
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    • 2019
  • This systematic review evaluates the clinical effectiveness of acupuncture related to improvement in quality of life and problems after Percutaneous Coronary Intervention(PCI). We searched papers in many databases, including National Discovery for Science Leaders(NDSL), Koreanstudies Information Service System(KISS), Oriental Medicine Advanced Searching Integrated System(OASIS), Research Information Sharing Service(RISS), Public/Publisher MEDLINE(Pubmed), Embase, Cochranelibrary, Chinese Academic Journals(CAJ), Japan Science and Technology Agency(J-STAGE). Initially, 161 studies were found. Of these, 141 studies were excluded following abstract screening. After the remaining 20 papers were scanned, 5 RCTs were selected and analyzed. Among these 5 RCTs, HAMD(Hamilton Rating Scale for Depression) is significantly effective in 1 RCT. In 2 RCTs, LVEF(Left Ventricular Ejection Fraction) is significantly effective. In 2 RCTs, 6MWT(Six-Minute Walk Test) is significantly effective. The review of 5 studies suggests that acupuncture after PCI can be effective in many problems occured after PCI. However, This study couldn't conduct a meta-analysis due to the differences in interventions. Therefore, we hope that systematic reviews with meta-analysis will be published.

Dual-Task Training Effect on Cognitive and Body Function, β-amyloid Levels in Alzheimer's Dementia Patients: A Randomized Controlled Trial

  • Nam, Seung-Min;Kim, Seong-gil
    • The Journal of Korean Physical Therapy
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    • v.33 no.3
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    • pp.136-141
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    • 2021
  • Purpose: Dementia is a disease in which cognitive function declines, leading to deterioration of body functions and activities of daily living. The purpose of this study is to explore the effects of dual-task training, including cognitive tasks, on cognitive and body function and β-amyloid levels in Alzheimer's dementia patients. Methods: 34 inpatients diagnosed with Alzheimer's dementia at a nursing hospital located in South Korea. The patients were randomly divided into a dual-task group (n=16) and a single-task group (n=18). Each group was trained for 30 minutes three times a week for eight weeks. The MMSE-K was used to measure the patients' cognitive function. To assess the patients' static balance ability, their LOS was measured using BioRescue. while dynamic balance was measured using the BBS. The 10MWT were conducted to evaluate the patients' walking ability. Blood analysis was performed to measure levels of β-amyloid. Results: Both groups exhibited statistically significant improvements in gait function after the training (p<0.05). The dual-task group exhibited statistically significant differences in cognitive function, static and dynamic balance function, and β-amyloid levels after training (p<0.05). A significant difference was observed between the two groups (p<0.05). Conclusion: Dual-task training were found to be effective in improving cognitive and bodily functioning and reducing β-amyloid levels in Alzheimer's dementia patients. Thus, this may be suggested as an effective exercise method for the treatment and early prevention of Alzheimer's dementia.

Effect of an Intensive Rehabilitation Program on Physical Activity and Wearing Satisfaction in Traumatic Lower Limb Amputees -A Retrospective Study- (집중재활프로그램이 하지 절단 환자의 신체활동 및 의지 착용감에 미치는 영향 -후향적 연구-)

  • Kim, Jin-Hong;Hong, Ye-Ji;Kim, Yu-Ri;Lee, Gang-Pyo
    • PNF and Movement
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    • v.18 no.3
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    • pp.453-463
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    • 2020
  • Purpose: This study aimed to investigate the effect of an intensively rehabilitation program on the gait, balance, functional performance, and wearing satisfaction of patients with traumatic lower extremity amputations caused by industrial accidents. Methods: In this study, the anonymized electronic medical records of individuals who participated in the intensive rehabilitation program (among those who were admitted to the hospital belonging to the Labor Welfare Corporation) due to an industrial accident from August 2018 to September 2019 were collected. As a result, the records of 12 subjects meeting the screening criteria were analyzed. Results: According to the time of application to the intensive rehabilitation program, the 10 Meter Walk Test (10MWT) (p < 0.01), Berg Balance Scale (BBS) (p < 0.01), Timed Up and Go Test (TUG) (p = 0.01), the L Test of Functional Mobility (L-test) (p < 0.01), Prosthetic Limb Users Survey of Mobility (Plus-M) (p < 0.01), and Houghton Score Question (HSQ) (p < 0.01) values significantly improved with time. Conclusion: This study confirmed the positive effect of an intensive rehabilitation program on the gait, balance, functional performance, and wearing satisfaction of patients with traumatic lower extremity amputations caused by industrial accidents. However, this study was limited by the absence of a control group, and, thus, it highlights the need for more extensive research with a large sample.