• The Journal of Korea Robotics Society
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• v.1 no.1
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• pp.81-88
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• 2006

Control of a robot manipulator in contact with the environment is usually conducted by the direct feedback control using a force-torque sensor or the indirect impedance control. In these methods, however, the control algorithms become complicated and the performance of position and force control cannot be improved because of the mechanical properties of the passive components. To cope with such problems, redundant actuation has been used to enhance the performance of position control and force control. In this research, a Double Actuator Unit (DAU) is proposed, with which the force control algorithm can be simplified and can make the robot ensure the safety during the external collision. The DAU is composed of two actuators; one controls the position and the other modulates the joint stiffness. Using this unit, it is possible to independently control the position and stiffness. The DAU based on the planetary gears is investigated in this paper. Performance using the DAU is also verified by various experiments. It is shown that the manipulator using this mechanism provides better safety during the impact with the environment by reducing the joint stiffness appropriately on detecting the collision of a manipulator.

• Journal of Power Electronics
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• v.13 no.6
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• pp.955-963
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• 2013

To acquire a performed and practical solution that is free from chattering, this study proposes the use of an adaptive super-twisting algorithm to drive a single-phase induction motor. Partial feedback linearization is applied before using a super-twisting algorithm to control the speed and stator currents. The load torque is considered an unknown but bounded disturbance. Therefore, a time-varying switching gain that does not require prior knowledge of the disturbance boundary is proposed. A simple sliding surface is formulated as the difference between the real and desired trajectories obtained from the indirect rotor flux oriented control strategy. To illustrate the effectiveness of the proposed control structure, an experimental setup around a digital signal processor (dS1104) is developed and several tests are performed.

• Journal of Korean language education
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• v.29 no.3
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• pp.197-225
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• 2018

The purpose of this study is to compare the difference in the interactions between beginning language learners and heritage learners on their forms based on the interaction hypothesis. In this study, three types of information gap activities were used to analyze Language Related Episodes (LREs) while investigating the interaction patterns in language use between four pairs (eight learners) of foreign learners and four pairs (eight learners) of English-speaking heritage learners. The result indicated that foreign learners had a high focus on form during interaction. In particular, they had a tendency to focus on vocabulary rather than grammar, and they conducted self-repair by examining and mostly adjusting their speech to postposition and tense. However, in the problem-solving process, they showed a limited ability in interaction, and thus directly asked others to settle the problem or resorted to using English due to their lack of ability to employ various communication strategies. However, heritage learners had a relatively low focus on form compared to foreign learners. Yet, they also focused more on vocabulary rather than grammar and conducted self-repair in interaction, especially for vocabulary. In addition, they were skillful at using various communication strategies such as indirect expressions, use of alternative words, evasion, and delaying, to expand speech and prevent communication breakdown. They focused less on grammar and mostly did not provide negative feedback in interaction.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.2
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• pp.123-141
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• 2009

Interregional migration is viewed as the most important component in regional population change in Korea. The purpose of this study is to analyze the structure of interrelationship among influential factors of interregional migration from the macro-viewpoint. During the period of 2000-05 the correlation between immigration and outmigration among 223 shi gun gu spatial unit was over 0.95, indicating that regions with high outmigration received high immigration. In this study the hypothesized cause-and-effect relationship among six influential factors of total migration flow was analyzed using path analysis. Based on the direct effect culturalwelfare environment has the biggest impact on immigration, while education environment and new housing environment are somewhat less and industrial-job opportunity environment the smallest impact. However based on the indirect effect, fiscal environment has the biggest impact on immigration, while industrial-job opportunity environment and infrastructure environment are somewhat less and new housing environment the smallest impact. If we consider the total effect, fiscal environment and cultural-welfare environment have the most significantly influenced on immigration. In particular, the influence of fiscal environment was remarkable in migration process through nonrecursive path and feedback loop.

• Journal of Home Health Care Nursing
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• v.3
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• pp.75-85
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• 1996

Nursing Intervention Classification(NIC) includes the 433 intervention lists to standardize the nursing language. Efforts to standardize and classify nursing care are important because they make explicit what has previously been implicit, assumed and unknown. NIC is a standardized language of both nurse-initiated and physician-initiated nursing treatments. Each of the 433 interventions has a label, definition and set of activities that a nurse does to carry it out. It defines the interventions performed by all nurses no matter what their setting or specialty. Principles of label, definition and activity construction were established so there is consistency across the classification. NIC was developed for following reasons; 1. Standandization of the nomen clature of nursing treatments. 2. Expansion of nursing knowledge about the links between diagnoses, treatments and outcomes. 3. Devlopment of nursing and health care information systems. 4. Teaching decision making to nursing students. 5. Determination of the costs of service provided by nurses. 6. Planning for resources needed in nursing practice settings. 7. Language to communicate the unigue function of nursing. 8. Articulation with the classification systems of other health care providers. The process of NIC development ; 1. Develop implement and evaluate an expert review process to evaluate feedback on specific interventions in NIC and to refine the interventions and classification as feedback indicates. 2. Define and validate indirect care interventions. 3. Refine, validate and publish the taxonomic grouping for the interventions. 4. Translate the classification into a coding system that can be used for computerization for articulation with other classifications and for reimbursement. 5. Construct an electronic version of NIC to help agencies in corporate the classifiaction into nursing information systems. 6. Implement and evaluate the use of the classification in a nursing information system in five different agencies. 7. Establish mechanisms to build nursing knowledge through the analysis of electronically retrievable clinical data. 8. Publish a second edition of the nursing interventions classification with taxonomic groupings and results of field testing. It is suggested that the following researches are needed to develp NIC in Korea. 1. To idenilfy the intervention lists in Korea. 2. Nursing resources to perform the nursing interventions. 3. Comparative study between Korea and U.S.A. on NIC. 4. Linkage among nursing diagnosis, nursing interventions and nursing outcomes. 5. Linkage between NIC and other health care information systems. 6. determine nursing costs on NIC.

• Phonetics and Speech Sciences
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• v.10 no.1
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• pp.75-81
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• 2018

Diplophonia is generally defined as the perception of more than one fundamental frequency component in a voice. Its perceptual aspect has traditionally been used to evaluate diplophonia because the perceptions can be easily evaluated, but there are limitations in the validity of the reliability of the intra- and inter-raters, examination situation, and variation of voice sample. Therefore, the purpose of this study is to confirm the reliability and accuracy of auditory perceptual evaluation by comparing non-invasive indirect assessment methods (sound waveform and EGG analysis), and to identify their usefulness with diplophonia. A total of 28 diplophonic voices and 39 non-periodic voices were assessed. Three raters assessed the diplophonia by performing an auditory perception evaluation and identifying the quasi-periodic perturbations of the acoustic waveform and EGG. Among the three discrimination methods, intra- and inter-rater reliability, sensitivity, specificity, accuracy, positive likelihood ratio, and negative likelihood ratio were examined, and the McNemar test was performed to compare the discriminant agreement. The accuracy of the auditory perceptual evaluation (86.57%) was not significantly different from that of sound waveform acoustic (88.06%), but it was significantly different from that of EGG (83.33%). The reading time (6.02 s) for the auditory perceptual evaluation was significantly different from that for sound waveform analysis (30.15 s) and EGG analysis (16.41 s). In the discrimination of diplophonia, auditory perceptual evaluation has sufficient reliability and accuracy as compared to sound waveform and EGG. Since immediate feedback is possible, auditory perceptual evaluation is more convenient. Therefore, it can continue to be used as a tool to discriminate diplophonia in clinical practice.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.512-523
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• 2014

The purpose of this study is to provide useful information for improving interaction between teacher and student by analysing gifted class in mathematics with the Flanders Category System. Research questions are as follow. In gifted class in mathematics, How is the result of analysis regarding interactions between the teacher and students, according to 1) Flanders' Coding system? 2) Flanders' language pattern? 3) Flanders' Index system? For this, 3 gifted classes in mathematics were recorded by video camera and analyzed by Advanced Flanders(AF) analysis program version 3.54. Results are as follow. 1) Code Category Analysis mostly consists of lecture, voluntary speaking and chaos, silence work. 2) Most class patterns are not in accordance with effective class pattern models. So teacher needs to accept student's opinion actively and give appropriate feedback. 3) In Indices Results, revised I/d ratio, teacher's question ratio, student's speaking ratio, Student question and wide answer ratio are higher than analysis standard, indirect ratio is lower than analysis standard.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.1
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• pp.105-113
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• 2017

Network externality can be defined as the effect that one user of a good or service has on the value of that product to other people. When a network externality is present, the value of a product or service is dependent on the number of others using it. There exist asymmetries in network externalities between the online and traditional offline marketing channels. Technological capabilities such as interactivity and real-time communications enable the creation of virtual communities. These user communities generate significant direct as well as indirect network externalities by creating added value through user ratings, reviews and feedback, which contributes to eliminate consumers' concern for buying products without the experience of 'touch and feel'. The offline channel offers much less scope for such community building, and consequently, almost no possibility for the creation of network externality. In this study, we analyze the effect of network externality on the competition between online and conventional offline marketing channels using game theory. To do this, we first set up a two-period game model to represent the competition between online and offline marketing channels under network externalities. Numerical analysis of the Nash equilibrium solutions of the game showed that the pricing strategies of online and offline channels heavily depend not only on the strength of network externality but on the relative efficiency of online channel. When the relative efficiency of online channel is high, the online channel can greatly benefit by the network externality. On the other hand, if the relative efficiency of online channel is low, the online channel may not benefit at all by the network externality.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.7
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• pp.335-343
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• 2006

We have designed the system that measure one channel ECG by two electrode and extract real-time EDR with more related resipiration and comportable to subject by using conductive textile. On the assumption that relation between RL electrode and potential measurement electrode is coupled with RC connected model, we designed RL drive output to feedback two electrode for reduction of common mode signal. The conductive textile which was used for two ECG electrode was offered more comfort during night sleep in bed than any other method using attachments. In the method of single-lead EDR, R wave point or QRS interval area could be used for EDR estimation in traditional method, it is, so to speak, the amplitude modulation(AM) method for EDR. Alternatively, R-R interval could be used for frequency modulation(FM) method based on Respiratory Sinus Arrhythmia(RSA). For evaluation of performance on AM EDR and FM EDR from 14 subject, ECG lead III was measured. Each EDR was compared with both temperature around nose(direct measurement of respiration) and respiration signal from thoracic belt(indirect measurement of respiration) on mean squared error(MSE), cross correlation(Xcorr), and Coherence. The upsampling interpolation technique of multirate signal processing is applied to interpolating data instead of cubic spline interpolation. As a result, we showed the real-time EDR extraction processing to be implemented at micro-controller.

• The Journal of the Korea Contents Association
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• v.16 no.7
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• pp.575-586
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• 2016

The purpose of this study was to investigate the influential factors of organizational cynicism of nurses in hospitals, and to examine data contributing the effective organizational management and the organizational effectiveness. Data were collected from 320 nurses working in a hospital in 2005. A total of 295 questionnaires were analyzed by the SPSS WIN 21.0. The leadership, job interdependence, job stress, positive and negative affectivity had significant effect on the organizational cynicism of hospital nurses. Also, the organizational cynicism had significant mediating effects on job satisfaction and organization commitment, and organizational climate showed significant indirect effects on the job satisfaction and organizational commitment. In conclusion, hospital managers and nursing directors need to adopt following strategies; open communication, friendly feedback, trust among staff, co-operation between departments and intra-departments, sharing information, creating joyful organizational climate, adequate organizational supports, fair compensation, and favorable organizational culture.