Background: Delivery workers repeatedly get in and out of trucks and walk or run to deliver packages during work. Iliotibial band syndrome (ITBS) is a well-known non-traumatic overuse injury of the lateral side of the knee caused by frequent knee flexion and extension. Hip muscle strength is among the factors that prevent lower extremity injuries. Although many studies have examined the relationship between ITBS and hip muscle strengths, there was no study comparing hip muscle strength and ratio between delivery workers with and without ITBS. Objects: This study aimed to compare hip muscle strength and hip internal/external rotator and adductor/abductor strength ratios between delivery workers with and without ITBS. Methods: Fourteen delivery workers with ITBS matched inclusion criteria in the present study among 20 participants. Because total sample size was required 28 subjects by G*power program (ver. 3.1.9.4; University of Trier), 14 delivery workers without ITBS were recruited. Hip muscle strengths were measured in a side-lying position using a Smart KEMA pulling sensor (KOREATECH Co. Ltd.). An independent t-test was used to compare hip muscle strengths and hip internal/external rotator and hip adductor/abductor strength ratios between delivery workers with and without ITBS. Results: The adductor/abductor strength ratio was significantly greater in delivery workers without ITBS than in those with ITBS (p < 0.05). The strengths of the hip abductor, hip adductor, hip internal rotator, hip external rotator, and the ratio of internal/external rotator strengths were not significantly different between the delivery workers with and without ITBS (p > 0.05). Conclusion: This study’s findings showed that delivery workers with ITBS had significantly lesser adductor/abductor strength ratio, while the strengths of the hip abductor and adductor muscles did not differ significantly. These results suggest that adductor/abductor strength ratio should be considered when evaluating and treating ITBS in delivery workers.

The objective of this study is to evaluate Flow-Pollutant load delivery ratio equations developed from rural watershed on main subwatersheds within Juam Lake. Two regression equations for BOD and three equations for T-P were evaluated on Bosung cheon, Dongbok cheon, Songgwang cheon, Naenam cheon, and Sinpyeon cheon. The results show that estimation of BOD delivery ratio using flow-delivery equation is reliable when relative composition of discharge load of pollutant sources of a watershed is similar to those of watershed where the equation developed. On the other hand, application of regression equation for T-P was feasible when the landuse pattern and relative composition of discharge load of pollutant sources of a watershed is similar to those of watershed where the equation developed.

The objective of this study is to provide pollutant loads delivery ratio for flow duration in Oenam-cheon watershed, which is upstream watershed of Juam Lake. To calculate the delivery ratio by flow duration, rating curves and discharge-loads curves using measured data were established, then Flow Duration Curve(FDC) and pollutant loads delivery ratio curves were constructed. The results show that the delivery ratios for BOD5 for abundant flow(Q95), ordinary flow(Q185), low flow(Q275), and drought flow(Q355) were 23.9, 12.7, 7.1, and 2.9%, respectively. The delivery ratios of same flow regime for T-N were 58.4, 31.2, 17.2 and 7.1%, respectively. While, the delivery ratios T-P were 17.3, 7.5, 3.4, and 1.1% respectively. In general, delivery ratio of high flow condition showed higher value due to the influence of nonpoint source pollution. Based on the study results, generalized equations were developed for delivery ratio and discharge per unit area, which could be used for ungaged watershed with similar pollution sources.

This study intends to estimate the best model parameters for predicting the water quality and discharge of the study area, and provide the basic data necessary for predicting the water quality and discharge and examining changes in water quality on the basis of the changes hydraulic and hydrological changes and pollutional load of the study area. Nakdong River was selected for analysis, and the water quality survey data necessary for parameter estimation was based on the monthly water quality data (discharge, BOD, T-N and T-P) between December 1, 2002 ~ November 31, 2002. The topographical characteristics factors of the study area were based on the 1/25,000 numerical map published by the National Geographic Information Institute and satellite photographs. The presumed course: It measured the most suitable parameter that could imitate surveyed water quality and discharge using the method of trial and error, in this part the first numerical value was the model parameter presented SWAT. The result of analisys showed that a relative error between surveyed value and the result of water quality imitation about BOD, T-N, T-P that examined by this study, discharge correction : R2=0.912, discharge verification : R2=0.838, correction and verification of BOD : R2=0.847, correction and verification of T-N : R2=0.712 and, correction and verification of T-P : R2=0.726 and, BOD : RK1, RK3, T-N : RS3, RS4, T-P : RS2, RS5, GWSOLP, discharge : ALPAHA_BF, GWQMN, CH_N(2), CN2, SOL_AWC have been considered as the factors of the water quality performed in this water quality simulation, that is, the most effective parameters on BOD, T-N and T-P. It is considered that it will be possible to apply the most optimal parameter to an analysis of the water quality and discharge simulation at study area in the goal year by examining the interaction of the parameters through the parameters sampling which are able to applicable to prediction of the water quality and discharge in the future, also the analysis on the basis of the hydrological conditions: an outflow or the character of a flow will be needed.