Holmium:YAG laser를 이용한 요관경하쇄석술의 초기 경험 : 기존의 쇄석술과의 결과 비교

구경완,노용수,김홍섭,양상국,나공찬 건국대학교 의과학연구소 2003 건국의과학학술지 Vol.13 No.-

Purpose: Holmium:YAG lasertripsy for the 33 patients with lower ureteral calculi compared the outcome with other results using Lithoclast and ultrasonic lithotripsy. Materials and Methods: Thirty-three patients with symptomatic urinary calculi underwent Holmium:YAG lasertripsy from March 1999 to December 2000. Twelve patients were treated with Ultrasonic lithotripsy and twenty-one patients with Lithoclast lithotripsy from April 1997 to October 1999. All calculi of the above patients were located in their lower ureters. The size of ureter stones was ranged from 3.5 mm to 12 mm (mean 6.54 mm). Results: The age of the patients ranged was from 19 to 62 years (me~n 35.7 years). After a single ureteroscopic lasertripsy calculi were conlpletely cleared in 83 % of the cases for the patients with lower ureter calculi. The immediate complications of lasertripsy were gross hematuria, fever, and flank pain. However in the long term follow up (up to 3 months after the procedures) there were no further complications, such as, vesicoureteral reflux or ureteral stricture. In other two lithotripsies Lithoclast and Ultrasonic lithotripsy accomplished calculi were completely cleared in 71 % and 74 % of cases respectively. But Holmium:Y AG lasertripsy is cleared in 94 % effectiveness. Holmium:Y AG lasertripsy is more effective than two other methods compared by stratified analysis that unmasking from confounding factors such as impacted situation. Conclusions: Lasertripsy with Holmium:Y AG laser is considered effective and safe procedure for the lower urinary calculi lithotripsy (Ultrasonic, Lithoclast).

Field application of Ergonomics Evaluation Tools (ALLA, AULA) for Farm Work

Yong-Ku Kong,Kyung-Hee Choi,Ji-Soo Park,Sung-Yong Lee,Dae Min Kim 대한인간공학회 2014 대한인간공학회 학술대회논문집 Vol.2014 No.11

Objective: The aim of this study is to analyze farm working postures using ergonomic evaluation tools (ALLA and AULA) and to examine the validity of each evaluation tool. Background: ALLA (Kong et al., 2010) and AULA (Kong et al., 2011) are whole-body posture evaluation tools in farm works, which were developed to prevent musculoskeltal disease caused by farm works which Method: Classifying farm works depending on the farming form. Farm working postures were evaluated by 19 ergonomic experts and using ergonomic evaluation tools in farm works, ALLA and AULA in order to evaluate working postures that are frequently observed in each type of farming. Results: The analysis result of farm working postures showed that the evaluation results of the experts and evaluation tools( ALLA and AULA) were similar. Conclusion: ALLA and AULA developed, based on the preceding studies, were appropriate for a postural evaluation of each body part in farm works. Although they aren’t perfect to apply a whole-body posture evaluation in farm works. his limitation could be solved by conducting a research on a whole-body posture evaluation, which integrates these two evaluation tools.

Optimal Grip Span of A-type Pliers in a Maximum Gripping Task

Yong-Ku Kong,Jin Woo Jung,Sangmin Kim,Heewoong Jung,Hakje Yoo,Dae-Min Kim,Hyun-Sung Kang 대한인간공학회 2013 大韓人間工學會誌 Vol.32 No.6

Objective: The objective of this study is designing an optimal hand tool through maximum grip force study accordance to the hand grip span. Background: In order to prevent musculoskeletal diseases, studies on hand tool design are proceeding based on grip strength, finger force, and contribution of individual finger force on total grip strength. However, experimental apparatus using a tool that is actually used in work place was almost non-existent. Method: 19 males were participated in an experiment. Using the load cell inserted real plier, finger force, grip strength, and subjective discomfort rate of both hands (dominant and non-dominant) were measured in 5 different hand grip span(45mm, 50mm, 60mm, 70mm, and 80mm). Results: There was significant difference(p<0.001) of total grip strength, individual finger force and subjective discomfort rating according to various hand grip span(45, 50, 60, 70, and 80mm). Also, statistically significant different(p<0.001) was shown between the dominant hand and non-dominant hand. In addition, individual finger force in maximum grip was in order of middle finger, ring finger, index finger, and little finger. Conclusion: Optimal grip span of pliers that exerting maximum grip strength is 50~60mm. Application: This finding is expected to be used for designing proper pliers.

A Design of Pliers in the Maximum Gripping Tasks

( Yong Ku Kong ),( Hyun Sung Kang ),( Dae Min Kim ),( Kyeong Hee Choi ) 한국감성과학회 2014 춘계학술대회 Vol.2014 No.-

Although automation of manufacturing environment, workers had to participated in most of processes and did manual task by using hand tools. Excessive use of hand tools also induced the WMSDs (i.e. carpal tunnel syndrome). Thus, optimal hand tool design for efficient use of grip strength is important factors for reducing the load on particular human body. In this study, a revised plier which can change gap from 45 to 80mm was applied to estimate grip strength, and resultant force. In the maximum gripping tasks, results showed that the effect of grip span on the total grip strength was statistically significant in the maximum gripping task (i.e. the 60mm grip span had a significantly higher total grip strength than the other grip spans). For resultant force task, the 60mm grip spans showed also significantly higher resultant force. The lowest subjective discomfort was observed in the 50mm span. So, 60mm grip span was optimal grip span for design optimal pliers. The results of this study are expected to be a basic guideline for optimal hand tool design so that reducing work-related musculoskeletal disorders related to hand tools

The effects of the Aging on Hand Strength and Ability to Control Force

Yong-Ku Kong(공용구),Dae-Min Kim(김대민),Sung-Yong Lee(이성용),Kyeong-Hee Choi(최경희) 한국경영과학회 2015 한국경영과학회 학술대회논문집 Vol.2015 No.4

A comparison of muscle force between EMG and AnyBody Simulation

Yong-Ku Kong,Dae-Min Kim,Min-Tae Seo,Hyun-Sung Kang 대한인간공학회 2012 대한인간공학회 학술대회논문집 Vol.2012 No.11

Objective: The purpose of this study is to compare predicted force of each muscle between EMG and AnyBody simulation. Background: AnyBody provides a default human body model and users are able to customize that model for their research purpose. Users have to validate default human body models by comparing simulation data and real experimental data before customizing it. Methods: One subject participated to conduct a simple task which is lifting a dumbbell. While participants were doing the lifting task, forearm muscle activities (EMGs) were collected in this study. A lifting posture and weight of dumbbell was applied to AnyBody program to develop a simulation model. Results: The finding of this study showed that the measured muscle forces (EMG) of each muscle were not coincident with the findings of simulation model. The result of modeling data showed the tendency of the higher force than measured EMG data in a lifting dumbbell task. Discussion: The reason of discrepancy between AnyBody simulation and EMG analysis may different anthropometric data which were used in AnyBody simulation with actual participants" anthropometric data. Therefore, default models in AnyBody might need to be modified to acquire a similar result of experiment.

Evaluation of pliers in a maximum gripping task

Yong-Ku Kong,Min-Tae Seo,Ji-Soo Kim,Hyun-Sung Kang 대한인간공학회 2013 대한인간공학회 학술대회논문집 Vol.2013 No.5

Objective: The objective of this study is to derive the optimal grip span of pliers in a maximum gripping task. Background: Although many previous studies have been performed for I-Type and cylinder-type handles and evaluated their various grip span size, there are only few studies regarding on A-Type handles such as pliers. Methods: A total of 25 males participated in this experiment and conducted maximum gripping task using custom-made pliers with three grip spans (50, 70, and 90㎜). The effects of grip spans on grip strength, muscle activity, and subjective discomfort were analyzed. Results: The experimental results showed that total grip strength of 50㎜ grip span had significantly higher than another grip spans. Subjective discomfort showed that the discomfort rating of radius side of the palm was higher than most other parts, significantly. The %MVC of the muscle has no significant difference in three grip span. Conclusion: It was recommended to use the 50mm grip span to exert the maximum grip strength with similar muscle activities in uses of pliers. Application: This finding is expected to be used as the basic data for designing proper pliers.

A Design of Pliers in the Maximum Gripping Tasks

Yong-Ku Kong,Hyun-Sung Kang,Dae-Min Kim,Kyeong-Hee Choi 대한인간공학회 2014 대한인간공학회 학술대회논문집 Vol.2014 No.5

Although automation of manufacturing environment, workers had to participated in most of processes and did manual task by using hand tools. Excessive use of hand tools also induced the WMSDs (i.e. carpal tunnel syndrome). Thus, optimal hand tool design for efficient use of grip strength is important factors for reducing the load on particular human body. In this study, a revised plier which can change gap from 45 to 80mm was applied to estimate grip strength, and resultant force. In the maximum g ripping tasks, results showed that the effect of grip span on the total grip strength was statistically significant in the maximum gripping task (i.e. the 60mm grip span had a significantly higher total grip strength than the other grip spans). For resultant force task, the 60mm grip spans showed also significantly higher resultant force. The lowest subjective discomfort was observed in the 50mm span. So, 60mm grip span was optimal grip span for design optimal pliers. The results of this study are expected to be a basic guideline for optimal hand tool design so that reducing work-related musculoskeletal disorders related to hand tools

Development and Evaluation of the Neck Supporter for Preventing Neck-related MSDs

Yong-Ku Kong,Jun-Goo Han 대한인간공학회 2011 大韓人間工學會誌 Vol.30 No.2

Many WMSDs(work-related-musculoskeletal disorders) have been reported in diverse industries and have also attracted much attention in recent years. Neck-related MSD is generally known as one of common WMSDs, especially it happens to workers who are working at the automobile assembly plants and/or shipyards. The awkward posture is considered as a main cause of neck-related MSDs. A neck supporter was developed to prevent neck-related MSDs, and 10 males were recruited to evaluate the newly developed neck supporter by measuring subjective discomfort ratings of whole body, shoulder, neck and neck-muscle activities. Muscle activities from four neck muscle groups(left/right sternocleidomastoid and upper/ middle trapezius) were measured while simulating an automobile assembly task. Results showed that the neck supporter help to significantly improve subjective discomfort for whole-body, shoulder as well as neck body parts. The analyses of muscular activities also showed that the activities of left/right sternocleidomastoid muscles were statistically decreased with the neck supporter in this study. The muscle activities of upper/middle trapezius in case of wearing the neck supporter were not significantly different with the muscle activities in case of no-wearing the neck supporter. Overall findings verified that the neck supporter might help to prevent neck-related MSDs based on the current study.

The effects of the Aging on Hand Strength and Ability to Control Force

Yong-Ku Kong(공용구),Dae-Min Kim(김대민),Sung-Yong Lee(이성용),Kyeong-Hee Choi(최경희) 대한산업공학회 2015 대한산업공학회 춘계학술대회논문집 Vol.2015 No.4