• Journal of the Korea Society of Computer and Information
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• v.28 no.12
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• pp.289-296
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• 2023

The purpose of this study aims to identify the key factors that contribute to successful online learning experiences for college students in the pre-course, during course, and post-course phases. A survey was conducted college students, and a total of 95 questionnaires were used for statistical analysis. The main findings revealed that in the pre-course phase, task value, academic self-efficacy, and control beliefs were significant factors. During course, interaction emerged as a crucial factor. Notably, students' satisfaction in the post-course phase is significantly influenced by academic self-efficacy and interaction. Understanding these factors will help inform the design and operation of effective college-level online courses to improve student experience and satisfaction.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.7C
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• pp.713-724
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• 2006

The purpose of this study is to design, implement and verify the pre-modulation filter with the variable -3dB cutoff frequency and linear phase response for bandlimiting the allocation of radio frequency bandwidth for PCM/FM transmission. For the design of this required filter, the digital FIR filter, DAC system and tuneable 2nd order LPF have been constructed and simulated according to the attenuation characteristic requirement of the amplitude frequency response by each stage. From these results, we have implemented the filter and verified the analog conversion hardware part which is composed of DAC system and tuneable 2nd order LPF for the interpolation of the discrete sequences. Especially this paper proposes and carries out the verification processes using the tone generator and the calibration procedures for more precise frequency response of the filter.

• Proceedings of the KIPE Conference
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• 2009.11a
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• pp.206-208
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• 2009

In this paper, a systematical controller design method for a twostage grid-connected photovoltaic power conditioning system is proposed. For a pre-stage boost converter to achieve the stable operation in the entire region of solar array, the digital resistive current mode controller is used. This algorithm is very simple to implement with a digital controller and there is no power stage parameter dependency in the controller design. For a post-stage single-phase full-bridge inverter, a PI controller with a feedforward compensation for the inner current control is employed. Furthermore, in case that the operating point of the solar array under varying environmental conditions is higher than the required voltage for the inverter current control, the bypass mode for the boost converter is possible for the more efficient operation. The proposed control scheme is validated through the experiment of the prototype two-stage power conditioning system hardware with a 200W solar array.

• IE interfaces
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• v.4 no.2
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• pp.81-92
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• 1991

A study showed that the two most important obstacles to assembly automation were that product designs are generally not assembly oriented and that most components cannot be handled automatically without problems. In the view of the importance of well designed product with high assemblability, a tool must be developed to pre-evaluate a product during design phase whether it can be assembled with minimum efforts. In this research, a prototype expert system for DFA has been developed that can be used to advise the designer of difficulties that his/her design presents for automatic handling during manufacture. This rule-based system has been implemented on an IBM personal computer, using the Texas Instruments' Personal Consultant Plus.

• Journal of Engineering Education Research
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• v.26 no.6
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• pp.19-29
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• 2023

This study aims to develop and apply a metaverse-based instructional design model for the education in science and technology. It analyzed the concept and characteristics of metaverse, existing non-contact education models, and major teaching strategies systematically. Based on the prior researches, an instructional design model using metaverse is developed that presents metaverse-related teaching strategies and design principles for the before-, during-, and after-lesson phases. Then, this model was applied to a project-based learning program, conducted a perception survey on instructors and learners, and revised the metaverse instructional design model based on the results of the survey. In the Metaverse Instructional Design Model, before-lesson phase is a physical and psychological preparation stage for class participation, which includes familiarization with the Metaverse learning environment, formation of expectations for education, and self-directed pre-learning. During the lesson, to effectively deliver the lesson content, it is necessary to build confidence in the learning environment, promote learning participation, provide reference materials, perform team projects and provide feedback, digest learning content, and transfer learning content. The after-lesson phase provides strategies for ongoing interaction between learners and mentors. This study introduces a new instructional design model that utilizes metaverse and shows the potential of metaverse-based education in science and technology. It also has important implications in that it provides practical guidelines for the effective design and implementation of metaverse-based education.

• Women's Health Nursing
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• v.7 no.1
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• pp.67-79
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• 2001

This study was designed to verify the effect of Doula-type-delivery nursing care on plasma $\beta$-endorphin, serum cortisol, related to delivery stress during labor, and postpartum anxiety of primipara by a quasi experiment(nonequivalent control group pretest-posttest design), from December, 1999 to August, 2000. The subjects of this experiment consisted of sixty eight primipara, with single gestation, full term, uncomplicated pregnancies, thirty three for the experimental group and thirty five for the control group. Their mean age was 26.1 years for the experimental group and 25.5 years for the control group. Their mean gestation period was 39.7 weeks for the experimental group and 40.1 weeks for the control group. As treatment, Doula-type-delivery nursing care was given for the experimental group. Data assessed plasma $\beta$-endorphin, serum cortisol during labor, and anxiety during postpartum. Plasma $\beta$-endorphin, serum cortisol were measured in the latent phase before treatment(pre-test) and the transition phase after treatment(posttest). Also, anxiety was measured in the latent phase before treatment(pre-test) and 24 hours postpartum after treatment(posttest). Data was analyzed by t-test, $x^2$-test, Repeated measures ANOVA with SAS Program. The results of this study were as follows; 1. Plasma $\beta$-endorphin was significantly elevated in the experimental group who were cared for with Doula-type-delivery nursing care during labor(P=.0463). 2. No significant group effects were found, but significant time effects were found for serum cortisol. 3. The postpartum anxiety of the experimental group was significantly lower than the control group(P=.0110). In conclusion, these findings indicate that Doula-type-delivery nursing care during labor could be effective in increasing maternal plasma $\beta$-endorphin and decreasing postpartum anxiety. Doula-type-delivery nursing care during labor could be applied as an effective nursing treatment for primipara.

• Journal of the Korea Convergence Society
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• v.12 no.1
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• pp.163-170
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• 2021

Smart-textronics technology which enables functional textiles has recently been applied in various fields such as smart clothes, smart home and smart health care, and a variety of smart-textronics products have been developed. In this context, the smart-textronics product development process is proposed based on the systematic participatory design method in this paper. The proposed method consists of two phases: in-depth interviews and analyzing. In the phase of in-depth interviews, participants are asked to create journey maps that include activities, pain points and emotional status and to generate solution ideas with sketches and simple prototypes. In the analyzing phase, design researchers investigate the participants' journey maps, and create personas by identifying critical characteristics with the behavior pattern analysis. Then, each persona's needs are linked with value elements of the E3 value framework. Finally, pre-survey was conducted to identify smart-textronics market and a smart sofa design is proceeded as the case study to show the applicability of the proposed method.

• Korean Journal of Construction Engineering and Management
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• v.4 no.3 s.15
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• pp.128-136
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• 2003

The contractors which execute the design-build project have difficulties in design management and contract administration in the pre-construction phase because they have managed construction projects focused on only construction phase so far. Moreover, they have to manage the design development stage without any contingency following-up various design revisions from the design reviews of outside experts. Therefore, the design management in the design development stage is a critical success facto. of the design-build project. The objective of this study is to structure the problems in the management skill for design development phase in the domestic design-build projects and to suggest a design development management method to settle the problems. To achieve these objectives, this study 1) analyzes the prior studies about the design-build procurement methods, 2) designs and performs a case study to embody the problems of the domestic design-build projects, and 3) proposes a method of design development management by analyzing the results of case study and interviewing experts.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.5 no.2
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• pp.181-195
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• 1998

This study is to evaluate the decubitus ulcer healing effect of occlusive dressing with hydrocolloid and traditional dry dressing for home care nursing clients. Study design was quasi-experimental pre-post test design. Control group(15 person) was treated decubitus wound with traditional dry gauze dressing, and experimental group(17 persons) was treated decubitus ulcer with occlusive dressing with hydrocolloid and calcium alginate(17 persons). Study period was from 8/1/97 to 12/31/97. Subject subjects was 17 males and 15 females with 2nd phase over decubitus ulcer aged 30 to 70 who have been registered as home care nursing clients in Nurse's Association in Seoul city. Outcome variables were stages, size of decubitus ulcer, pain at dressing time and exudate amount. Study result as follows. Occlusive dressing with hydrocolloid was superior to traditional gauze dressing decreasing ulcer size and phase, and shortening treatment period. Dressing change of occlusive dressing was easier than that of traditional gauze dressing. In conclusion, occlusive dressing was recommended to treat decubitus ulcer in home care patients even if hydrocolloid is expensive to gauze dressing because of treatment effect and easeness of dressing.

• Physical Therapy Rehabilitation Science
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• v.6 no.3
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• pp.106-112
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• 2017

Objective: Robot assisted gait training is implemented as part of therapy for the recovery of gait patterns in recent clinical fields, and the scope of implications are continuously increasing. However clear therapy protocols of robot assisted gait training are insufficent. The purpose of this study was to investigate the effects of robot-assisted gait training applied with guidance force on balance and gait performance in persons with hemiparetic stroke. Design: Two group pre-test post-test design. Methods: Nineteen persons were diagnosed with hemiparesis following stroke participated in this study. The participants were randomly assigned to the unilateral guidance group or bilateral guidance group to conduct robot-assisted gait training. All participants underwent robot-assisted gait training for twelve sessions (30 min/d, 3 d/wk for 4 weeks). They were assessed with gait parameters (gait velocity, cadence, step length, stance phase, and swing phase) using Optogait. This study also measured the dynamic gait index (DGI), the Berg balance scale (BBS) score, and timed up and go (TUG). Results: After training, BBS scores were was significantly increased in the bilateral training group than in the unilateral guidance group (p<0.05). Spatiotemporal parameters were significantly changed in the bilateral training group (gait speed, swing phase ratio, and stance phase ratio) compared to the unilateral training group (p<0.05). Conclusions: The results of this study suggest that robot-assisted gait training show feasibility in facilitating improvements in balance and gait performance for subacute hemiparetic stroke patients.