• Journal of Mechanical Science and Technology
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• v.18 no.4
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• pp.550-559
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• 2004

In this paper, a recursive formulation for generating the equations of motion of spatial mechanical systems is presented. The rigid bodies are replaced by a dynamically equivalent constrained system of particles which avoids introducing any rotational coordinates. For the open-chain system, the equations of motion are generated recursively along the serial chains using the concepts of linear and angular momenta Closed-chain systems are transformed to open-chain systems by cutting suitable kinematic joints and introducing cut-joint constraints. The formulation is used to carry out the dynamic analysis of multi-link five-point suspension. The results of the simulation demonstrate the generality and simplicity of the proposed dynamic formulation.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.3
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• pp.333-344
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• 2014

This is the survey paper on the role of kinematics in robot development. The robot is considered as a form of mechanical systems which includes closed-chain loop system, open-chain loop system and closed and open switching system. To analyze these systems, kinematic notations has been developed in kinematics of mechanical theory since 1955 and has been applied in robotics. Several kinematic notations including Denavit-Hartenberg notations have been reviewed. The status of development of the spherical motor which has a great impact on the future robot advancement has reviewed, and research activity on a spherical motor and its application to 3-D spatial mechanisms at UNIST is introduced. For the open and closed switching mechanical systems, the bipedal robots' walking theories using Zero Moment Point are reviewed. And current status regarding bipedal robots based on newly developed passive dynamic walking theory is reviewed with the research activity at UNIST on this subject.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.4
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• pp.485-492
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• 2014

PURPOSE: This study aimed to examine the pain, range of motion (ROM), upper extremity task performance, and functional levels of patients after rotator cuff repair according to the timing of a closed chain exercise thereby presenting basic data for an effective rehabilitation program. METHODS: The intervention was applied three times per week, one hour per day, for four weeks to 40 participants, 78 of whom had undergone rotator cuff repair. The participants were divided into four groups and assigned to usual general physical therapy and an open chain exercise. Group I consisted of the open chain exercise only. The closed chain exercise was applied to group II after the 4 times, group III after the 7 times, group IV after the 10 times. Measurement were used ROM, visual analogue scale (VAS), box and block test (BBT), and shoulder pain and disability index (SPADI). A one-way analysis of variance was conducted to test differences. RESULTS: There were significant differences in the internal/external rotation between group I and group II. The VAS significantly differed between group II and group I, group III, and group IV. The BBT results of group II and group I were significantly different compared to those of group IV. The SPADI significantly differed between group II and group I and between group II and group IV. CONCLUSION: The closed chain exercise was effective for patients following rotator cuff repair from the second week after active exercise was prescribed, verifying its applicability in rehabilitation programs.

• PNF and Movement
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• v.19 no.3
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• pp.423-433
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• 2021

Purpose: Proprioceptive neuromuscular facilitation (PNF) is a method for promoting functional movements by facilitating neuromuscular responses through the stimulation of proprioceptors in the body using spiral and diagonal patterns. Irradiation, a basic principle of PNF, is a phenomenon in which the muscle activity of a body part caused by resistance is increased or spread into muscles in other parts via their connected muscles. Resistance training can be divided by body alignment into closed and open chain exercises. Methods: In this study, 19 healthy men in their 20s and 30s were selected as subjects. They performed PNF hip flexion, abduction, and internal rotation motions on their dominant side in an open chain exercise posture in which the nondominant sole was away from the wall, and in a closed chain exercise posture in which the sole was fixed to the wall. The nondominant leg's muscle activity was measured while resistance was maintained with applied pressure at 0%, 25%, 50%, 75%, and 100% of the maximum muscle strength in the last range of motions. A two-way analysis of variance (ANOVA) was conducted for a comparative analysis of the contralateral leg's muscle activity according to the chain exercise postures and the intensity of resistance intensity during PNF hip flexion, abduction, and internal rotation. In addition, an independent sample T-test was conducted for a comparative analysis of each chain exercise posture according to the intensity of resistance. A one-way ANOVA and a Scheffe post-hoc test were also performed to analyze the contralateral leg's muscle activity according to the intensity of resistance in the closed and open chain exercise postures. Results: Results of the two-way ANOVA found that the gluteus medius and the biceps femoris had statistically significant differences in both the chain exercise postures and resistance intensity (p<0.05), and that the vastus medialis and the gastrocnemius did not exhibit statistically significant differences in the chain exercise postures (p>0.05) but showed statistically significant differences in resistance intensity (p<0.05). As a result of the independent sample T-test, the application of the PNF hip flexion-abduction-internal rotation pattern led to a statistically significant difference in the contralateral gluteus medius during the closed chain exercise posture (p<0.05). According to the results of the one-way ANOVA and the Scheffe post-analysis, statistically significant differences were observed in the gluteus medius at 50%, biceps femoris at 75%, vastus medialis at 100%, and gastrocnemius at 100% during the closed chain exercise posture based on a resistance intensity of 0% (p<0.05). In the open chain exercise posture, statistically significant differences were found in the gluteus medius at 50%, biceps femoris at 50%, and vastus medialis at 75% based on the resistance intensity of 0% (p<0.05). In the same posture, there was no significant difference in the gastrocnemius's resistance intensity (p>0.05). Conclusion: When the PNF leg pattern is applied, each muscle requires effective chain exercise postures and resistance intensity to generate the contralateral leg muscle's irradiation.

• Bulletin of the Korean Chemical Society
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• v.12 no.6
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• pp.666-673
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• 1991

The elongation of the chain length at 2'position of aminothiazolylacetamido group of cephalosporin antibiotics was achieved. The derivatives with elongated side chain at 2'position were successfully synthesis and their in vitro activities were evaluated. It is indicated that there is an optimum range of the chain length in order to exhibit higher biological activities. This result could open a possibility for the development of the cephalosporin antibiotics with higher activities by further variation of the substituents at other positions. The cephalosporin derivatives with a simple (relatively non-functionalized) side chain as well as with a linear extended side chain were also prepared. Low activities of these derivatives led to a conclusion that either simple (non-functionalized) change or linear elongation of the side chain does not enhance the antibacterial activities.

• Journal of Information Technology Services
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• v.20 no.6
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• pp.63-81
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• 2021

Joint financial network of Korea Financial Telecommunications and Clearings Institute, which is an essential facility with a natural monopoly, maintained its closedness as monopoly/public utility model, but it has evolved in the form of open banking in order to obtain domestic fintech competitiveness in the rapidly changing digital financial ecosystem such as the acceleration of Big Blur. In accordance with digital transformation strategy of financial institutions, various ICT companies are actively participating in the financial industries, which has been exclusive to banks, through the link technology called Open API. For this reason, there has been a significant change in the financial service supply chain in which ICT companies participate as users. The level of security in the financial service supply chain is determined based on the weakest part of the individual components according to the law of minimum. In addition, there is a perceived risk of personal information and financial information leakage among the main factors that affect users' intention to accept services, and appropriate protective measures against perceived security risks can be a catalyst, which increases the acceptance of open banking. Therefore, this is a study on factors affecting the introduction of open banking to achieve financial innovation by developing an open banking security control model for financial institutions, as a protective measures to user organizations, from the perspectives of cyber financial security and customer information protection, respectively, and surveying financial security experts. It is expected, from this study, that effective information protection measures will be derived to protect the rights and interests of financial customers and will help promote open banking.

• Journal of Satellite, Information and Communications
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• v.10 no.4
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• pp.39-45
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• 2015

Satellite communication is high-speed large-capacity transmission in such a manner as to communicate with satellites in the chamber, and there is a wide area communication, but is not the security of the information. To compensate for this, AES encryption was applied to the CTR and CBC mode. Also, Blockage channel using a Markov chain to determine the impact caused by obstacles such as trees or buildings between the transmitter and the receiver was composed of Urban and Open Environment. The results of analyzing the performance of satellite communications over a high-speed link-based simulation, If applying encryption, performance of security is complementary but performance of the BER was aggravated and In the Open Environment fewer obstacles confirmed the BER performance is improved than the Urban Environment many obstacles.

• Journal of the Korean Operations Research and Management Science Society
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• v.40 no.3
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• pp.73-95
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• 2015

Firms have reexamined and restructured their supply chain based on a long-term and partnership perspective as a firm's competitive advantage increasingly relies on its supply chain capability. A number of scholar works has provided evidence to support the positive effects of supply chain collaboration; however, the relationship between collaboration and performance is still inconclusive. This study refuses to have blinded faith on supply chain collaboration, but rather this paper suggests that the contribution of collaboration to supply chain performance improvement can be limited and vary along the contextual characteristics of a buyer-supplier relationship. Moreover, we argue that the relationship between supply chain collaboration and performance can be curvilinear. This paper provides and test hypotheses regarding the relationship between supply chain collaboration and performance. By using data of the Manufacturing Panel Survey (MPS), this study empirically validates the hypotheses. Overall, the results of the study support our hypotheses about a limited contribution of supply chain collaboration to manufacturing performance, which is opposite to a conventional expectation. Particularly, the effects of supply chain collaboration differ depending on the dimensions of performance such as customer satisfaction, quality, cost, delivery, and flexibility as well as the dependency in the buyer-supplier relationship. Moreover, the results of the study indicate that supply chain collaboration and performance may have curvilinear relationships in a certain context. Through a comprehensive model and empirical evidence, this study presents a better understanding of supply chain collaboration and provokes an open discussion about the effects of collaboration. This study also provides insightful implications for managers of buyers as well as suppliers who wish to foster stronger supply chain performance via a deep buyer-supplier relationship and collaboration.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.33
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• pp.247-275
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• 2007

This paper is to propose the Direction for the institutional improvement of Financial Supply Chain Management(FSCM) Solution which are currently coming into operation under Global e-Trading Platform. The Financial Supply Chain compromise the entire trade processes and information that manage a trader's cash, Accounts payable and receivable, Risk, working capital, and so on in international trade transaction. From a buyer's perspective, this involves the full procurement-to-payment process. For the seller, it is the order-to-cash cycle. Bolero provides the party concerned a e-trade platform which conformed to these fundamental pre-requisites to underpin fully electronic trade. But this FSCM solution have failed to provide the efficient platform to effectively manage the process of Global e-Trade because it does not correspond with e-Trade environment. Therefore, present FSCM system need the institutional improvement as follows: AA) Strengthening the role of the correspondent Bank under e-Trade System, BB) Extending the function of e-Trade intermediary institution, CC) The introduction of Trade Insurance System, etc. So, by streamlining and automating these processes on an open and flexible platform, The party concerned can optimize their trade transaction and maintain better relations with their business partners

• Journal of Distribution Science
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• v.19 no.7
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• pp.19-27
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• 2021

Purpose: Former research has argued that organizations in distribution channels face several issues to make a better team-based system. The purpose of the present research is to measure between employee's job performance and three major issues which disturb a solid team system. Research design, data and methodology: Scant past studies are available to guide for team practitioners which elements should be eliminated to improve team performance. To achieve this goal, the present authors obtained 267 US workers in distribution channels and conducted ANOVA test to measure the relationship between three team issues (Free-rider, Trust, and Communication) and job performance. Results: Our statistical findings clearly suggests that there was a statistically recognizable difference at the significance level of probability between the mean value of employees' job performance and three major issues, showing the high degree of job performance can be occurred by eliminating three major team issues. Conclusions: Therefore, the present research concludes that it is necessary that team-based management in the supply chain should focus on removing free-rider issues and also adopt open communication lines to overcome team-building challenges due to communication. Above all else, the ability to increase trust can be enhanced via task delegation and more team members' engagement.