• Korean Journal of Applied Biomechanics
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• v.32 no.1
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• pp.31-36
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• 2022

Objective: The purpose of this study was to investigate muscle activation according to the four strap lengths in the TRX plank exercise to provide scientific and accurate data on effective training methods. Method: Twenty healthy men who had at least 6 months of weight training experience and could fully adjusted plank exercise, were participate in this study (age: 25.2 ± 3.7 yrs., height: 174.2 ± 3.9 cm., weight: 71.2 ± 9 kg). To pursue the study purpose, surface electrodes were attached to trunk muscles (pectoralis major, rectus abdominis, external oblique, internal oblique, erector spinae, latissimus dorsi) and lower extramity muscles (gluteus maximus, rectus femoris, gastrocnemius), and the muscle activity was measured using 11-channel electromyography equipment. In order to verify the muscle activation according to the four strap lengths during TRX plank exercise, an one-way ANOVA with repeated measure was used with statistical significance level set at as α=.05. Results: First, there were statistically significant differences in pectoralis major, rectus abdominis, external oblique, internal oblique, and erector spinae among TRX strap lengths. Second, there were statistically significant differences in gluteus maximus, rectus femoris, and gastrocnemius among TRX strap lengths. Third, even though no statistically significant difference found in latissimus dorsi, but increased muscle activation tendency was showed as the length of the strap increased. Conclusion: From the results of this study, it may be possible that TRX exercise prevent injuries and improve lower extremity muscle as well as trunk muscles by setting appropriate length of strap.

• Fashion & Textile Research Journal
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• v.24 no.3
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• pp.289-302
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• 2022

This study aimed to provide information to establish a service strategy in cross-border e-commerce through an assessment of consumer satisfaction with a cross-border shopping channel and "amazon global store" managed by 11street, a domestic e-commerce corporation. The influence of brand familiarity with amazon as a global retail brand was tested. The mediating roles of the perceived value and risk of both cross-border shopping and amazon global store were investigated; the moderating role of the domestic e-commerce corporation was also studied. An empirical study was conducted on consumers who had experience using the amazon global store managed by 11street. To verify the hypothesis, data from 200 people was analyzed using PROCESS macro 4.0. The results indicated that familiarity with global brands did not have a direct effect on consumer satisfaction; the effect of global retail brand familiarity on consumer satisfaction was mediated only by the perceived value of cross-border shopping and amazon global store, not by the perceived risks. E-commerce corporate credibility showed a moderated mediation effect by mediating functional values of the amazon global store. For consumer groups with a credibility level of medium and above, the interaction effect of brand familiarity and corporate credibility was significant.

• Korean Journal of Applied Biomechanics
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• v.33 no.1
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• pp.1-9
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• 2023

Objective: This study identifies the difference among the heights of a chair's backrest (High, Mid, No), the biomechanical changes chair users undergo over time, and the variables that can measure musculoskeletal disorders, eventually providing information on the appropriate type of backrest. Method: Eleven healthy subjects in their 20s and 30s who had no experience with musculoskeletal disorders or surgical operations within the last 6 months participated in this study. Computer typing tasks were randomly designated and performed according to the type of chair backrest, and evaluation was performed for Flexion-Relaxation Ratio (FRR) analysis after the computer typing tasks. This study used eight infrared cameras (sampling rate: 100 Hz) and nine-channel electromyography (sampling rate: 1,000 Hz). ANOVA with repeated measures was conducted to verify the results, with the statistical significance level being α = .05. Results: Although there was no significant difference in craniovertebral angle (CVA), this study showed time and interaction effects depending on the height of the backrest (p<.05). When working without the backrest, the head-spine angle was lower compared to the chairs with backrest, based on the computer work. As for the head angle, the higher the back of the chair was, the less the head flexion and the body angle became, whereas the body flexion became less when there was a backrest. In addition, the body flexion increased over time in all types of backrests (p<.05). The muscle activity of the upper body tended to be high in the high backrest chair. On the other hand, a lower muscle activity was found with a low backrest. Conclusion: These results show that a chair is more ergonomic when the body angle is correctly set without bending and when it is supported by a low backrest. Accordingly, this study determines that the backrest affects shoulder and neck musculoskeletal disorders during typing and that medium-height backrest chairs can help prevent musculoskeletal disorders, contrary to the expectation that high-backrest chairs are preferable.

• Human Ecology Research
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• v.61 no.3
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• pp.389-399
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• 2023

Sustainable fashion products have different characteristics from typical fashion products. Therefore, this study focuses on shoes while exploring the expansion and development of sustainable fashion consumption as well as consumers' perceptions of the sustainability approaches practiced by shoe companies. In-depth interviews were conducted with 24 consumers, who had purchased sustainable shoes, in order to understand their purchase decision-making process and consumption characteristics, using the seven stages of the EBM model. In the "need recognition" stage, the survey participants' social background and family influences were categorized as macro factors, while their personal background influences were categorized as micro factors. In the "evaluation of alternatives" stage, participants reconfirmed whether or not to make a purchase based on the product's properties, such as price, brand value, and offered services. In the "purchase" stage, participants' purchase channels were determined according to their preferences as well as the selection pattern they followed until the final purchase within the chosen channel. In the "consumption" stage, the start of product ownership coincides with the start of using the products after making a purchase. In the "post-purchase assessment" stage, higher positive experiences led to a higher repurchase intention of sustainable shoes, while negative experiences caused participants to defer consumption and made them experience a sense of guilt for failing to consume sustainably. During the "post-purchase behavior" stage, which focused on the categories that the customers prioritized, many participants spread information about sustainable fashion to specific individuals through active online WOM behavior.

• The Journal of Economics, Marketing and Management
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• v.6 no.4
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• pp.51-64
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• 2018

Purpose - This study is intended to look into the influences of restaurant consumers' e-WOM information communication on product perception risk, benefit and WOM effect. Research design, data, and Methodology - To achieve this, a survey was empirically carried out to 426 restaurant consumers. Results - The findings are as follows. First, the influence of e-WOM on product perception risk showed that WOM information sender characteristics, WOM information recipient characteristics and online community had a statistically significant positive influence on product perception risk. Second, the influence of e-WOM on product risk benefit showed that WOM information sender characteristics, WOM information recipient characteristics and online communication had a statistically significant positive influence on product risk benefit. Third, WOM risk perception had a statistically significant positive influence on WOM acceptance. Fourth, WOM risk benefit had a statistically significant positive influence on WOM effect. Conclusions - As for the above-mentioned findings, the communication between e-WOM sender and recipient had a positive influence on the product evaluation and attitude change in the restaurant industry, and the WOM effect had an influence on the financial performance and non-financial performance. The communication attaches importance to a direct using and tasting experience due to the nature of restaurant industry when it is simultaneously performed as a positive mechanism between sender and recipient through each channel of these factors. But the e-WOM culture can lead to the WOM effect when both sender and recipient share the persuasive communicability in reality that diversifies communication methods, having a positive influence on the management performance.

• Korean Journal of Applied Biomechanics
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• v.34 no.1
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• pp.25-33
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• 2024

Objective: The purpose of this study was to compare the lower extremity muscle activity and knee joint load according to movement speed conditions during the barbell back squat. Method: Nine males with resistance training experience participated in this study. Participants performed the barbell back squat in three conditions (Standard, Fast, and Slow) differing movement speed. During the barbell back squat, muscle activity of the rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM), biceps femoris long head (BFL), semitendinosus (ST), gluteus maximus (GM), gastrocnemius (GCN), and tibialis anterior (TA) was collected using an 8 channel wireless EMG system. The peak flexion angle of the lower extremity joints and the peak resultant joint force in each direction of the knee joint were calculated using eight motion capture cameras and ground reaction force plates. This study was to used the Friedman test and the Wilcoxon signed rank test, to compare lower extremity muscle activity and peak resultant joint force at knee joint according to movement speed conditions during the barbell back squat, and the statistical significance level was set at .01. Results: In the downward phase of the barbell back squat, the RF and TA showed the higher muscle activity in the fast condition, and in the upward phase, RF, VL, VM, BFL, ST, GM, and TA showed the higher muscle activity in the fast condition. As a results, analyzing of the load on the knee joint, in the downward phase, and in the upward phase, the higher peak compressive force of the knee joint was showed in the fast condition. Conclusion: The barbell back squat with fast movement speed was more effective due to increased muscle activity of lower extremity, but one must be careful of knee joint injuries because the load on the knee joint may increase during the barbell back squat with fast movement speed.

• Nuclear Engineering and Technology
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• v.56 no.8
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• pp.2974-2989
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• 2024

The one-dimensional Two-Fluid concept uses an area-average approach to simplify the time and phase-averaged Two-Fluid conservation equations, making it more suitable for addressing difficulties at an industrial scale. Nevertheless, the mathematical framework has inherent weaknesses due to the loss of details throughout the averaging procedures. This limitation makes the conventional model inappropriate for some flow regimes, where short-wavelength perturbations experience uncontrolled amplification, leading to solutions that need to be physically accurate. The critical factor in resolving this problem is the integration of closure relations. These relationships play a crucial function in reintroducing essential physical characteristics, thus correcting the loss that occurs during averaging and guaranteeing the stability of the model. To improve the accuracy of predictions, it is essential to assess the stability and grid dependence of one-dimensional formulations, which are particularly affected by closure relations and numerical schemes. The current research presented in the text focuses on improving the well-posedness of the TFM, specifically within the TRACE code, which is widely utilized for nuclear reactor safety assessments. Incorporating a bubble collision model in the momentum equations is demonstrated to enhance the TFM's resilience, especially in scenarios with high void fractions where conventional TFMs may face challenges. The analysis presents a linear stability analysis performed for the transient one-dimensional Two-Fluid Model of system code TRACE within the framework of vertically dispersed flows. The main emphasis is on evaluating the stability characteristics of the model while also acknowledging its susceptibility to closure relations and numerical techniques.

• Journal of Broadcast Engineering
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• v.17 no.4
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• pp.640-658
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• 2012

One of the existing terrestrial multi-channel DTV service frameworks, called KoreaView, provides four programs, composed of MPEG-2 based one HD video and H.264/AVC based three SD videos within one single 6MHz frequency bandwidth. However the additional 3 SD videos can not provide enough quality due to its reduced spatial resolution and low target bitrates. In this paper, we propose a framework, which is called a terrestrial multi-channel high quality hybrid DTV service, to overcome such a weakness of KoreaView services. In the proposed framework, the three additional SD videos are encoded based on an H.264/SVC Spatial Base layer, which is compliant with H.264/AVC, and are delivered via broadcasting networks. On the other hand, and the corresponding three additional HD videos are encoded based on an H.264/SVC Spatial Enhancement layer, which are transmitted over broadband networks such as Internet, thus allowing the three additional videos for users with better quality of experience. In order to verify the effectiveness of the proposed framework, various experimental results are provided for real video contents being used for DTV services. First, the experimental results show that, when the SD sequences are encoded by the H.264/SVC Spatial Base layer at a target bitrate of 1.5Mbps, the resulting PSNR values are ranged from 34.5dB to 42.9dB, which is a sufficient level of service quality. Also it is noted that 690kbps-8,200kbps are needed for the HD test sequences when they are encoded in the H.264/SVC Spatial Enhancement layer at similar PSNR values for the same HD sequences encoded by MPEG-2 at a target bitrate of 12 Mbps.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.528-536
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• 2009

Recently, the importance of IPTV providing multimedia service over IP based networks managed to provide the required level of quality of service and experience, security, interactivity and reliability has been gradually increasing by the commercialization of its service. However, the original purposes of IPTV service - contents are produced and consumed anytime, anywhere, and over any device at the same time - have not been satisfied by service providers because most services offered by service providers depend on closed IPTV platform. In this paper, we propose an open IPTV service platform that an individual or small company can easily produce contents and offer IPTV service independently from the existing closed IPTV platform.. The proposed IPTV platform exploits overlay multicast scheme to offer reasonable service under the environment where network bandwidth and processor resource are limited. It also uses CDN-like scheme to ensure the quality of transmitted contents. The performance evaluation shows that the proposed IPTV platform has the possibility of being an open IPTV platform considering its results such as the quality of transmitted contents, the transmission rate, the channel zapping time, and so on. It also shows that proposed IPTV platform could be applied to real IPTV service with continuous enhancement of its functions and user interfaces.

• Journal of Korean Academy of Nursing Administration
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• v.5 no.3
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• pp.445-462
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• 1999

The purpose of this study is to provide some basic data for the direction of nursing education and practice to prevent nursing malpractice as investgating perception of the nurse on the nursing malpractice and its case. Data were collected from 450 nurse working in four general hospitals which were located in Chonbuk province from November 9 to 21, 1998 through questionnare. The structured instruments developed by the reseacher were used for collecting data. The Results were as follows: 1) As for the cognition of the nursing malpractice case, the transfusion accident was 37.3%, the side-effects of KCL injection(19.3%), hymen rupture by uterus cancer test, the side-effects of aminophyllin injections on dyspnea patient and the others were 10% below. 2) With regard to the channel of the perception of the nursing malpractice case, mass-communication was taken first and followed through by neighbors, In-service education, school education, continuing education 3) As for the direct${\cdot}$indirect experience of the nursing malpractice case, transfusion accident was 51.3%, the fall of NPO patient after an operation 40.1%, the side-effect of KCL injection 32.5%, suicide of the psychiatric patient 32.5%, and the others were 30% below. 4) The possibility of nursing malpractice case was an average 2.57(${\pm}$0.91) and the highest was the fall of the NPO patient after an operation. 5) The perception on the responsibility of the nursing malpractice in its case was indicated as a joint-fault in ten nursing malpractice instances. As compared to the real decision, nurse's perception of the responsibility in the fall of the NPO patient after an operation, the side-effect of KCL injection, the tracheal edema of the patient who had a thyroid operation, the suicide of psychiatric patient, the hymen rupture by uterus cancer test accorded real decisions. But the other cases were different from the real decisions. These cases were perceived as ones of joint fault even in cases determined as Dr's single fault cases or those in which both doctor and nurse were declared free of fault. 6) Knowledge levels of the nursing malpractice, school education and In-service education were perceived as low but anxiety levels of the malpractice were high. 7) With regard to the countmeasure of the hospital after nursing malpractice, the rate answered as "the practice settled the accident temporarily and forced the person in charge to be punished" was highest. In conclusion, the level of the cognition of the clinical nurse on nursing malpractice cases was low. As nurses' perception on the responsibility of the nursing malpractice case was compared to the real decision, there was a difference in five cases out of the ten cases.