• Korean Journal of Applied Biomechanics
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• v.17 no.1
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• pp.145-153
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• 2007

The purpose of this study is to compare and analyze the phase-by-phase elapsed time, the COG, the body joint angle changes and the angular velocities of each phase of Handspring Salto Forward Piked performed by 4 college gymnasts through 3D movement analysis program. 1. The average elapsed time for each phase was .13sec for Phase 1, .18sec for Phase 2, .4sec for Phase 3, and .3sec for Phase 5. The elapsed time for Phase 1 to Phase 3 handspring was .35sec on average and the elapsed time for Phase 4 to Phase 5 handspring salto forward piked was .7sec on average. And so it showed that the whole elapsed time was 1.44sec. 2. The average horizontal changes of COG were 93.2 cm at E1, 138. 5 cm at E2, 215.7 cm at E3, 369.2 cm at E4, 450.7 cm at E5, and 553.1 cm at E6. The average vertical changes of COG were 83.1 cm at E1, 71.3 cm at E2, 78.9 cm at E3, 93.7 cm at E4, 150.8 cm at E5, and 97.2 cm at E6. 3. The average shoulder joint angles at each phase were 131.6 deg at E1, 153.5 deg at E2, 135.4 deg at E3, 113.4 deg at E4, 39.6 deg at E5, and 67.5 deg at E6. And the average hip joint angles at each phase were 82.2 deg at E1, 60 deg at E2, 101.9 deg at E3, 161.2 deg at E4, 97.7 deg at E5, and 167 deg at E6. 4. The average shoulder joint angular velocities at each phase were 130.9deg/s E1, 73.1 deg/s at E2, -133.9 deg/s at E3, -194.4 deg/s at E4, 29.4 deg/s at E5, and -50.1 deg/s at E6. And the average hip joint angular velocities at each phase were -154.7 deg/s E1, -96.5 deg/s at E2, 495.9 deg/s at E3, 281.5 deg/s at E4, 90.3 deg/s at E5, and 181.7 deg/s at E6. The results shows that, as for the performance of handspring salto forward piked, it is important to move in short time and horizontally from the hop step to the point to place the hands on the floor and jump, and to stretch the hip joints as much as possible after the displacement of the hands and to keep the hip joints stretched and high in the vertical position at the takeoff. And it is also important to bend the shoulder joints and the hip joints fast and spin as much as possible after the takeoff, and to decrease the speed of spinning by bending he shoulder joints and the hip joints quickly after the highest point of COG and make a stable landing.

• Earthquakes and Structures
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• v.12 no.2
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• pp.201-211
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• 2017

This paper experimentally investigates the effect of yield strength of reinforcing bars and stirrups on the seismic performance of reinforced concrete (RC) circular piers. Reversed cyclic loading tests of nine-large scale specimens with longitudinal and transverse reinforcement of different yield strengths (varying between HRB335, HRB500E and HRB600 rebars) were conducted. The test parameters include the yield strength and amount of longitudinal and transverse reinforcement. The results indicate that the adoption of high-strength steel (HSS) reinforcement HRB500E and HRB600 (to replace HRB335) as longitudinal bars without reducing the steel area (i.e., equal volume replacement) is found to increase the moment resistance (as expected) and the total deformation capacity while reducing the residual displacement, ductility and energy dissipation capacity to some extent. Higher strength stirrups enhance the ductility and energy dissipation capacity of RC bridge piers. While the product of steel yield strength and reinforcement ratio ($f_y{\rho}_s$) is kept constant (i.e., equal strength replacement), the piers with higher yield strength longitudinal bars are found to achieve as good seismic performance as when lower strength bars are used. When higher yield strength transverse reinforcement is to be used to maintain equal strength, reducing bar diameter is found to be a better approach than increasing the tie spacing.

• Journal of Korea Society of Industrial Information Systems
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• v.11 no.5
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• pp.245-260
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• 2006

The e-learning market in korea has been growing rapidly over the past several years. We selects the variables well matched to service quality of e-learning site on the basis of independent variables of this study, sets the models as adding the factors newly noticed such as convenience of site use in e-learning. We also see the significance of the relationships between service quality of e-learning site, personal performance, customer satisfaction and customer's reuse intention.

• Korean Journal of Agricultural Science
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• v.47 no.2
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• pp.255-262
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• 2020

The aim of this study was to investigate the growth performance between two different crossbred strains of Korean native chickens denoted as 1E and 2E with a white semibroiler (LL) from hatch to d-84 post-hatch. A total of 450 one-day-old chicks were randomly distributed into cages which included 15 replicate cages each for 1E and 2E with 9 replicate cages for LL. A three phase feeding program was used as a starter (Day 1 - 35; crude protein [CP] 20.3%; metabolizable energy [ME] 3,059 kcal·kg^-1), grower (Day 36 - 56; CP 18.6%; ME 3,123 kcal·kg^-1) and finisher (Day 57 - 84; CP 16.7%; ME 3,187 kcal·kg^-1). The results revealed that LL had a higher (p < 0.05) BW during d-8 to d-84 compared with the other two cross breed groups. A higher (p < 0.05) ADG was observed from the LL during the entire period except from d-1 to d-14 and d-71 to d-84 when compared with 1E and 2E. Shank length did not vary (p > 0.05) between the strains, despite LL having a SL that was 2.86% higher (p < 0.05) when compared with the other strains from d-15 to d-21 post-hatch, and 1E had a SL that was 2.28% (p < 0.05) higher when compared with the other strains during the first week of the experiment.

• The Journal of Information Systems
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• v.23 no.2
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• pp.91-107
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• 2014

In computer-mediated idea generation where contributions can be anonymous, the ability to accurately monitor performances is limited, inducing social loafing. Prior research has suggested that social loafing is likely an important factor in reducing task performance. Researchers have theorized that loafing could be minimized if clear performance feedback is provided. Our prior study evidences a substantial performance gain by the provision of real time performance information about who is contributing and who is not. However, our prior study incorporated the quantity feedback only to create a larger pool of ideas based on the long-standing assumption (i.e., quantity breeds quality), not considering the quality feedback. As a result, taking advantage of anonymity in the form of pseudonymity, individuals in almost all groups exhibited a tendency of self-presentation by capitalizing on ideas of which quality was low and even frivolous (i.e., junk comments) toward the later stages of the session. Thus, we have learned that the quantity performance feedback alone does not have enough restrictiveness to consistently control the performance behavior throughout the session. Since a process chart allows participants to monitor process variation by comparing new performance data to past performance data, we incorporated real-time visual process performance feedback to reveal performance histories by connecting the sequence of idea quality scores in a time-series format. Using this environment, a laboratory experiment was conducted with five-member groups that examined the influence of both identifiability (i.e., anonymity versus pseudonymity) and process performance feedback (i.e., yes or no) in a $2{\times}2$ factorial design. The result showed that groups in the process performance feedback treatment outperformed groups in the no feedback treatment. Additionally, process performance feedback and identifiability interacted such that groups in the process performance feedback/pseudonymity treatment had the highest performance. The implications of these findings for future research, as well as the implications for the design of group idea generation procedures are discussed.

• Journal of Service Research and Studies
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• v.11 no.2
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• pp.37-66
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• 2021

This study aims to provide self-development opportunities to hair salons service workers through e-learning and provide the foundation of sustainable hair salons management by cultivating good talents to hair salons service business executives. In particular, the factors affecting e-learning achievement are identified according to learner characteristics to see whether these factors affect the satisfaction of e-learning learners and also affect the performance of management. The results of the study are summarized as follows. As a result of hypotheses testing on the relationship between e-learning learning environment and e-learning satisfaction, it was found that the higher the level of e-learning content quality is, the higher the satisfaction of e-learning is, the higher the satisfaction of e-learning is, and that the higher the quality level of the support infrastructure is, the higher the satisfaction of e-learning is. The results of the hypotheses testing on the moderating effect of learner factors showed that the influence of the quality of the support infrastructure on the e-learning satisfaction differs according to the level of the learner's goal consciousness. However, it was found that the influence of content quality on e-learning satisfaction according to the level of the learners goal awareness, the influence of content quality on e-learning satisfaction according to the level of the aggressiveness of the learners learning attitude, and the influence of the quality of the support infrastructure on the e-learning satisfaction according to the level of the aggressiveness of learners learning attitude were found to identically demonstrate no moderating effects. The results of hypotheses testing on the relationships among e-Learning performance show that the higher the satisfaction of e-learning was, the higher the customer orientation was, and the higher the satisfaction of e-learning was, the higher the contribution of management performance was, and the higher the customer orientation was, the higher the contribution of management performance was. The implications of this study are as follows. First, the actual path of realiting e-learning performance could be identified that is this study provided organizational decision makers involved in the hair salons service operations with practical guidance for the introduction and expansion of successful educational systems. Second, the e-learning environment derived from the theoretical background is different from the e-learning environment required by the learners.

• Journal of Environmental Health Sciences
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• v.39 no.2
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• pp.187-195
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• 2013

Objectives: For the practical application of the dielectric barrier discharge plasma reactor, a plasma reactor able to manage large volumes of water is needed. This study investigated the possibility of the practical application of a multi-plasma reactor which is a scaled-up version of a single plasma reactor. Methods: The multi-plasma reactor consists of several high-voltage transformers and plasma modules (discharge, ground electrodes and quartz dielectric tubes). The effects of water characteristics such as voltage (30-120 V), air flow rate (1-5 l/min), number of high-voltage transformers and plasma modules, and water quality on Escherichia coli (E. coli) disinfection and decrease of COD and $UV_{254}$ absorbance were investigated. Results: The experimental results showed that at a voltage of over 80 V, most of the E. coli were disinfected within 90 seconds. E. coli inactivation was not affected by the air flow rate. E. coli disinfection in the multiplasma process showed the traditional log-linear form of the disinfection curve. E. coli inactivation performance by transformer 3-Reactor 5 and transformer 3-Reactor 3 were similar. The disinfection performance of the UV process was affected by artificial sewage water. However, the plasma process was less affected by the artificial sewage within the standards for effluent water quality. Conclusions: Disinfection performance with several low voltages and plasma modules of three to five in number applied to the plasma process was higher than that concentrating a small amount of high voltage through a single plasma reactor. Removal of COD, $UV_{254}$ absorbance, and E. coli disinfection with the plasma process were better than with the UV process.

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.143-149
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• 2007

The experiment was conducted to examine the effects of dietary organic selenium and vitamin E on weight gain, feed intake, feed conversion, and selenium retention in meat of broiler chickens. For each growth phase, the basal diet was supplemented with 0 (control), vitamin E 150 IU/kg and the combination of 1.2 ppm Se from selenium yeast (SY) and vitamin E 100, 150, 200 and 300 IU/kg. Weight gain was significantly higher in supplemental control and vitamin E 150 compared to the combination of 1.2 ppm SY and vitamin E 150 IU during day 1 to 21. Feed intake significantly(P<0.05) increased in supplemental vitamin E 150 compared to the combination of 1.2 ppm SY and vitamin E 150 and 200 IU during day 1 to 21. Feed intake was significantly(P<0.05) higher in control compared to that of combination of 1.2 ppm SY and vitamin E 200 IU during day 21 to 35. However feed conversion was not affected in supplemental vitamin E and SY during day 1 to 35. Selenium concentrations of breast muscle and liver tissue significantly increased (P<0.05) in supplemental combination of 1.2 ppm SY and vitamin E compared to the control and vitamin E 150 IU. TBARS of control and vitamin E 150 IU were significantly (P<0.05) higher in day 3 than day 1, but the combination of Se 1.2 ppm and vitamin E of TBARS had no difference during day 1 to 3. TBARS in day 3 was significantly (P<0.05) lower in supplemental combination of Se 1.2 ppm and vitamin E than control and vitamin E 150 IU.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.1 s.160
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• pp.95-106
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• 2007

The purpose of this study is to investigate the relationship between the implementation and the performance of the eSCM in internet shopping malls, and to suggest collaborated strategy for internet shopping malls. We performed the surveys of suppliers for 3 fashion-specialized internet shopping malls and 3 general internet shopping mall. Additional surveys was performed by surveying the shopping mall merchandisers to research the differences of understandings on the performance of the eSCM between shopping malls and their suppliers. Total 143 questionnaries were distributed and collected from January 23 to February 28, 2006 and analyzed by SPSS 10.0. The results are as follows; 1) the efficiency of eSCM is related the factors of partnership and information, and among the subordinated factors the understanding and support of the top management, good communications, product and operating information sharing were find out to be significant. 2) The effectiveness of eSCM is influenced by the organizational and partnership factor. As the subordinated factors, the understanding and supports of the top management, the participations of members, good communications, good relationship and supports, and the technology level of eSCM were identified as significant. 3) Examining the differences of understandings on the performance of eSCM between the suppliers and the shopping mall merchandisers, the suppliers and the merchandisers show different opinions on the operating efficiency, and the customer service.

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.667-673
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• 2009

This study has carried out to evaluate the performance of single (electrolysis, UV and ultrasonic process) and complex process (Electrolysis+UV, UV+Ultrasonic and Electrolysis+Ultrasonic) for the purpose of disinfection of Escherichia coli in water. The order of disinfection performance for E. coli in single process lie in: Electrolysis ${\fallingdotseq}$ UV >> ultrasonic process. OH radical was not produced in single disinfection process. Among the three kinds of complex process, disinfection performance of the Electrolysis+UV was higher than that of the other process (UV+Ultrasonic and Electrolysis+Ultrasonic). It demonstrated a synergetic effect between the UV and electrolysis. When the use of $Na_2SO_4$ as electrolyte instead of NaCl, current increase or more reaction time was needed for the complete disinfection. The disinfection performance of pre-electrolysis (20 W, 30sec) and post-UV (10 W, 30 sec) was higher than that of the simultaneous electrolysis+UV process at same electric power (30 W, 30 second).