• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1155-1162
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• 2003

Nanocrystalline semiconductor film electrodes have been prepared by sintering three different sizes of TiO₂ nanoparticle sols on conducting indium-tin-oxide (ITO) glass substrate. The electrochemical and photoelectrochemical properties of the prepared electrodes were comparatively investigated. The particle sizes, surface morphologies and crystallinities of the films were studied by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. Cyclic voltammetry and capacitance measurements in the dark implies the formation of depletion layer in the semiconductor films which was usually neglected in the previous studies and shows that flat band potential ($E_{fb}$

• Bulletin of the Korean Chemical Society
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• v.9 no.3
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• pp.137-143
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• 1988

We have investigated the infrared spectra for carbon monoxide chemisorbed on silica supported ruthenium with and without potassium coating within the frequency range of 1800-2200 $cm^{-1}$ at various ruthenium concentrations and CO pressures. For the system without potassium coating, three bands were observed in the infrared spectra when CO was adsorbed on both the reduced and oxidized form of supported ruthenium. However, the relative intensities of these three bands were found to have no interdependence. Therefore, we have assigned each of these bands as arising from the CO stretching vibration for carbon monoxide molecules adsorbed on the Ru sites of different nature. On coating with potassium, the 2030 $cm^{-1}$ band observed for the system without potassium coating was found to suffer red shift by 10-30 $cm^{-1}$ and we conclude that this bathochromic shift is caused by enhancement in the capability of back donation of electrons from the metal atom to the antibonding ${\pi}{\ast}$ orbitals of CO due to the presence of potassium.

• Journal of Astronomy and Space Sciences
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• v.36 no.3
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• pp.133-147
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• 2019

Challenging Minisatellite Payload (CHAMP) satellite magnetic data are used to investigate the latitudinal variation of the storm-time meso-scale field-aligned currents by defining a new metric called the FAC range. Three major geomagnetic storm events are considered. Alongside SymH, the possible contributions from solar wind dynamic pressure and interplanetary magnetic field (IMF) $B_Z$ are also investigated. The results show that the new metric predicts the latitudinal variation of FACs better than previous studies. As expected, the equatorward expansion and poleward retreat are observed during the storm main phase and recovery phase respectively. The equatorward shift is prominent on the northern duskside, at ${\sim}58^{\circ}$ coinciding with the minimum SymH and dayside at ${\sim}59^{\circ}$ compared to dawnside and nightside respectively. The latitudinal shift of FAC range is better correlated to IMF $B_Z$ in northern hemisphere dusk-dawn magnetic local time (MLT) sectors than in southern hemisphere. The FAC range latitudinal shifts responds better to dynamic pressure in the duskside northern hemisphere and dawnside southern hemisphere than in southern hemisphere dusk sector and northern hemisphere dawn sector respectively. FAC range exhibits a good correlation with dynamic pressure in the dayside (nightside) southern (northern) hemispheres depicting possible electrodynamic similarity at day-night MLT sectors in the opposite hemispheres.

• Journal of Pharmacopuncture
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• v.27 no.3
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• pp.199-210
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• 2024

Objectives: Few studies have examined the impact of healthy sleep among general workers on individuals and society. Therefore, the status and risk factors of sleep disturbances among general workers were investigated. In addition, this study assessed the degree to which cold and heat symptoms are associated with sleep disturbances. Methods: A nationwide cross-sectional study was conducted through an online questionnaire focused on sleep disturbances of the general public in 2021. The degree of cold-heat pattern Identification (CHPI) of the general public was also surveyed. Descriptive statistics and multivariate logistic regression were used to derive the study results. Results: Data from 2,822 workers out of 3,900 valid questionnaires were analyzed. Approximately half of the respondents (49.93%) had sleep disturbances. Among the types of work, self-employed, two-shift work, and working more than 53 hours were associated with sleep disturbances. Sleep disturbances were positively associated with six cold and heat symptoms: three cold symptoms (coldness of the abdomen, coldness of body, and pale face) and three heat symptoms (body feverishness, feverishness of the limbs, and drinking cold water). Conclusion: Customized policies to maintain healthy work are needed for self-employed work, two-shift work, and long working hours, which are risk factors for workers' sleep disturbances. In addition, medical personnel can effectively diagnose and treat sleep disturbances considering the worker's cold and heat symptoms.

• Journal of Korean Clinical Nursing Research
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• v.26 no.1
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• pp.117-130
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• 2020

Purpose: This study aimed to develop a bedside nursing shift report protocol and evaluate the effect of the protocol in a tertiary hospital in South Korea. Methods: The bedside nursing handoff protocol with patient engagement was developed based on the literature review and the validation of an expert group. The effect of the protocol on clinical implication was tested in three medical-surgical units in a tertiary hospital. Outcomes were assessed by patient perception, nurse perception, and reporting time. Data collected from June to August in 2018 and analyzed with descriptive statistics and One-way ANOVA using SPSS version 25.0. Results: The bedside nursing shift report protocol with patient engagement consisted of two steps: nurse to nurse report and bedside report with patients. Nurse's perception with patient engagement was significantly increased after applying protocol (F=17.85, p<.001). Patient's perception was significantly improved in the areas of discharge plan (F=7.86, p<.001), health information privacy (F=4.46, p=.012) and identify attending nurse (F=3.19, p=.042). There were no differences in reporting time between the bedside nursing shift report and a traditional shift report (F=0.61, p=.054). Conclusion: Patient perception was significantly increased, while nurse perception was not different after applying this protocol. For the change in the perception of nurses, education may be preceded to improve nurses' competence for the bedside shift report. Furthermore, the support in enough nurse staffing should be needed for encouraging the bedside shift report. The bedside shift report may enhance patient engagement. Therefore it may improve patient safety and health outcome in clinics.

• Health Communication
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• v.12 no.1
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• pp.97-110
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• 2017

Purpose: This study is an overview of the experiences of nurses who have participated in a communication education program which was designed to develop proper change-of-shift dialogues. The goal of this program was to improve the communication competencies of outgoing and incoming nurses during handover and takeover of their shifts. Methods: The materials used in this study to analyze the experiences qualitatively were transcripts from narrative interviews with seven nurse participants. The education program consisted of two rounds of change-of-shift simulations by pairs of nurses, planning of a forthcoming change-of-shift, three lectures on ideal dialogue patterns, and time for video feedback. Afterwards the participants' experiences of the program were evaluated generally, highlighting the positive and the negative aspects, and how this educational experiences might affect their future change-of-shift activities. Results: High practicability, originality, professionalism, and effectiveness were some of the positive assessments made by the nurse participants. In addition, they pointed out that the sample video in which two professors performed an ideal handover and takeover and the paper kardex were both quite unrealistic. The location of the change-of-shift simulation was also unfamiliar so it needed to be supplemented. However, most of the nurses took for granted that such a communication education program is necessary and that it will provide a substantial help in their future job performance. In this regard they recommended the program to all related hospitals and nursing schools. Conclusion: The results of this study could be applied to other forms of communication education programs regardless of the specific area where communication takes place.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.181-184
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• 2005

Operating conditions of photovoltaic power generator is very sensitive to the PV modules. The PV module's control is an importance issue in the removing DC ripple noise. In this paper, the phase-shifted-carrier technique, which is a new three-step dc-dc power multi-converter schemes, is applied to solar generator system to improve the output current waveform. The novel type of three-step dc-dc converter presented has many features such as the good output waveform, high efficiency, low switching losses, low acoustic noise. The circuit configuration is constructed by the conventional full-bridge type converter circuit using the isolated DC power supply for which the solar cell is very suitable. In the end, a circuit design for understanding three-step dc-dc converter and new solar power system were presented

• The Journal of Advanced Prosthodontics
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• v.5 no.3
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• pp.262-269
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• 2013

PURPOSE. Perceived color of ceramics changes by the spectral power distribution of ambient light. This study aimed to quantify the amount of shifts in color and color coordinates of clinically simulated seven all-ceramics due to the switch of three ambient light sources using a human vision simulating spectroradiometer. MATERIALS AND METHODS. CIE color coordinates, such as $L^*$, $a^*$ and $b^*$, of ceramic specimens were measured under three light sources, which simulate the CIE standard illuminant D65 (daylight), A (incandescent lamp), and F9 (fluorescent lamp). Shifts in color and color coordinate by the switch of lights were determined. Influence of the switched light (D65 to A, or D65 to F9), shade of veneer ceramics (A2 or A3), and brand of ceramics on the shifts was analyzed by a three-way ANOVA. RESULTS. Shifts in color and color coordinates were influenced by three factors (P<.05). Color shifts by the switch to A were in the range of 5.9 to 7.7 ${\Delta}E{^*}_{ab}$ units, and those by the switch to F9 were 7.7 to 10.2; all of which were unacceptable (${\Delta}E{^*}_{ab}$ > 5.5). When switched to A, CIE $a^*$ increased (${\Delta}a^*$: 5.6 to 7.6), however, CIE $b^*$ increased (${\Delta}b^*$: 4.9 to 7.8) when switched to F9. CONCLUSION. Clinically simulated ceramics demonstrated clinically unacceptable color shifts according to the switches in ambient lights based on spectroradiometric readings. Therefore, shade matching and compatibility evaluation should be performed considering ambient lighting conditions and should be done under most relevant lighting condition.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.723-729
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• 2005

Traditional statistical process control(SPC) applied to discrete part industry in the form of control charts can look for and eliminate assignable causes by process monitoring. On the other hand, engineering process control(EPC) applied to the process industry in the form of feedback control can maintain the process output on the target by continual adjustment of input variable. This study presents controlling and monitoring rules adopted variable sampling interval(VSI) to change sampling intervals in a predetermined fashion on the predicted process levels for integrated EPC and SPC systems. Twelve rules classified by EPC schemes(MMSE, constrained PI, bounded or deadband adjustment policy) and type of sampling interval combined with EWMA chart of SPC are proposed under IMA(1,1) disturbance model and zero-order (responsive) dynamic system. The properties of twelve control rules under three patterns of process change(sudden shift, drift and random shift) are evaluated and discussed through simulation and control rules for integrated VSI EPC and SPC systems are recommended.

• Journal of Korea Multimedia Society
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• v.7 no.12
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• pp.1745-1753
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• 2004

A method of estimating the pose of a three-dimensional object from a set of two-dimensioal images based on parametric eigenspace method is proposed. A Gaussian blurred edge image is used as an input image instead of the original image itself as has been used previously. The set of input images is compressed using K-L transformation. By comparing the estimation errors for the original, blurred original, edge, and blurred edge images, we show that blurring with the Gaussian function and the use of edge images enhance the data compression ratio and decrease the resulting from smoothing the trajectory in the parametric eigenspace, thereby allowing better pose estimation to be achieved than that obtainable using the original images as it is. The proposed method is shown to have improved efficiency, especially in cases with occlusion, position shift, and illumination variation. The results of the pose angle estimation show that the blurred edge image has the mean absolute errors of the pose angle in the measure of 4.09 degrees less for occlusion and 3.827 degrees less for position shift than that of the original image.