• Journal of Korean Clinical Health Science
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• v.8 no.1
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• pp.1362-1368
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• 2020

Purpose. In this study, The change of the accommodation function due to the use of a smartphone was objectively evaluated using an Auto Refractokeratometer and was to investigate the effect of accommodation response and microfluctuations of accommodation on stable fatigue. Methods. Twenty subjects (20 males, 20 females) who had no abnormalities in ophthalmic disease and strabismus, diplopia, suppression, convergence and ocular movement, and corrected visual acuity and unaided visual acuity of 0.8 or more were performed. The average age of the participants is (21.78 ± 1.78) years old. The refractive power of the eye was measured using an Auto Refractokeratometer (Speedy-i K-model, Righton Mfg Co. Tokyo Japan), and the equivalent spherical power was automatically calculated from the measured refractive power. The accommodation response amount was calculated for the accommodation stimulation amount in 8 steps in 0.5D increments from + 0.50D to -3.00D in the calculated equivalent spherical power. The microfluctuations of accommodation in the high frequency region was calculated according to the change in the amount of the accommodation stimulus. At this time, the spectral power of the microfluctuations of accommodation was analyzed by Fast Fourier Transformation (FFT). Results. After using the smartphone, it was found that the accommodation response to accommodation stimulation decreased and the microfluctuations of accommodation increased. Conclusions. It can be said that the use of a smartphone affects the accommodation response and the microfluctuations of accommodation, thereby causing a accommodative stable fatigue. Therefore, it is thought that the use of a smartphone for a long time may bring about a change in the accommodation function.

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.3 s.22
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• pp.73-82
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• 2005

This paper describes shock waveform synthesis methods for a shock response spectnlm over a short time interval with which intereference between parts within a test item is increased to perform a sufficient shock test for damage or malfunction which may be caused by the interference between parts, and a digital filter for obtaining a shock response history required for the shock waveform synthesis and a digital inverse filter for restoration by inversely using the digital filter. The time at which the maximax value occurs in the response history is detected in order to establish a delay time which is one of the parameters in the wavelet, on the condition that the natural frequency of SDOF system with a Q (quality factor) of 10 equals to the wavelet frequency of the zero delay wavelet input. A shock response spectrum over a short time interval and an abrupt change in the acceleration for an instant are illustrated as features of the synthesized waveform.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.1
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• pp.43-52
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• 2021

According to several seismic design standards, a ground motion time history should be selected similar to the design response spectrum, or a ground motion time history should be modified by matching procedure to the design response spectrum through the time-domain method. For the response spectrum matching procedure, appropriate seed ground motions need to be selected to maintain recorded earthquake accelerogram characteristics. However, there are no specific criteria for selecting the seed ground motions for applying this methodology. In this study, the characteristics of ground motion time histories between seed motions and spectral matched motions were compared. Intensity measures used in the design were compared, and their change by spectral matching procedure was quantified. In addition, the seed ground motion sets were determined according to the response spectrum shape, and these sets analyzed the response of nonlinear and equivalent linear single degrees of freedom systems to present the seed motion selection conditions for spectral matching. As a result, several considerations for applying the time domain spectral matching method were presented.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.1
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• pp.33-42
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• 2021

The design response spectrum presented in the seismic design standard reflects the characteristics of the tectonic environment at a site. However, since the design response spectrum does not represent the ground motion with a specific earthquake magnitude or distance, input ground motions for response history analysis need to be selected reasonably. It is appropriate to use observed ground motions recorded in Korea for the seismic design. However, recently recorded ground motions in the Gyeongju (2016) or Pohang (2017) earthquakes are not compatible with the design response spectrum. Therefore, it is necessary to convert the recorded ground motion in Korea to a model similar to the design response spectrum. In this study, several approaches to adjust the spectral acceleration level at each period range were tested. These are the intrinsic and scattering attenuation considering the earthquake environment, magnitude, distance change by the green function method, and a rupture propagation direction's directivity effect. Using these variables, the amplification ratio for the representative natural period was regressed. Finally, the optimum condition compatible with the design response spectrum was suggested, and the validation was performed by converting the recorded ground motion.

• Korean Journal of Psychosomatic Medicine
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• v.31 no.1
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• pp.19-24
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• 2023

Objectives : Biofeedback is a useful non-pharmacological treatment for panic disorder (PD), but no studies have identified physiological markers related to the treatment response. This study investigated predictors of the treatment response for biofeedback in patients with PD. Methods : A retrospective study based on the electronic medical records of 372 adult patients with PD was performed. Patients received biofeedback treatment at least once, and physiological markers including heart rate, heart rate variability, respiratory rate, skin conductance, skin temperature, and electromyography were collected before the treatment began. The patients were classified as responders or non-responders based on the change in Clinical Global Impression-Severity (CGI-S) score. Results : The response rate to biofeedback treatment was 30.4%. Multivariable logistic regression analysis revealed that a higher CGI-S score at baseline and fewer benzodiazepine prescriptions were associated with a better response to biofeedback treatment. According to subgroup analyses, the baseline CGI-S score, dose of benzodiazepines, and skin conductance are candidate predictors of the response to biofeedback treatment in men, while only baseline disease severity was associated with the treatment response in women. Conclusions : The present results suggest that skin conductance may be target marker and predictor for biofeedback in male patients with PD.

• Journal of Oral Medicine and Pain
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• v.41 no.4
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• pp.161-168
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• 2016

Purpose: Patients who suffer from rheumatic arthritis, fibromyalgia, other various inflammatory diseases and musculoskeletal disorders, which are all similar to temporomandibular disorders (TMD), have been complaining about changes in the level and type of pain in response to changes in weather conditions for a long time. Through an investigation about pain perception in TMD patients in response to weather conditions, our primary objective was to develop base materials for future studies on change in pain in response to meteorological factors. Methods: Among patients who presented with TMD to Department of Oral Medicine, Pusan National University Dental Hospital from August to October 2016, one hundred consecutive TMD patients diagnosed with TMDs according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) were recruited for the study and 28 patients were excluded according to exclusion criteria. Survey was done with the questionnaire and investigated whether there was any difference in incidence and level of pain in TMD patients between non-rainy and rainy days. Results: Among a total of 72 samples, 4 patients reported change in pain on rainy days rather than non-rainy days. Two patients from chronic group (joint and complex subgroup) reported increased pain on rainy days rather than non-rainy days but it was not statistically significant (p>0.05). One patient from chronic/muscle group reported the change in pain characteristics while pain intensity remained unchanged. One patient from acute/complex group reported decreased pain intensity. In comparison of the patients who reported increased pain on rainy days between acute and chronic groups, there were two reported cases and were both from chronic group only. There was a significantly higher chance of reporting increased pain on rainy days in chronic group than acute group (p<0.001). Conclusions: It is considered that TMD patients couldn't perceive the change in pain well in response to weather change on rainy days but some chronic patients could perceive the increase in pain in rainy days.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.206-214
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• 2020

This study examined the correlation between the respiratory pattern change (RPC) and abdominal mobility (AM) according to the positive result of the subjective lumbar instability factor (SLIF) in people with chronic low back pain (CLBP). Thirty-six adults with CLBP participated in this study. Twenty-eight items of the SLIFs were examined, and the subjects were divided into three groups according to the positive response numbers (PRN). After the change lists were scored, three RPC scores [costo-diaphragmatic RPC (CDRPC), breath hold change (BHC), and total RPC (TRPC)] were obtained. The abdominal mobility (AM) was measured between the maximal inspiration and exhalation at the xiphoid (AM1) and the 10^th rib (AM2) level of the trunk. The results showed that the RPC score and AM were compared according to the positive response number of SLIF, and the relationship between them was analyzed. A positive correlation was observed between the SLIF positive response number and CDRPC score, BHC score, and total RPC score, and a negative correlation was observed between the SLIFs positive response number and AM1 and AM2. Based on the results of this study, the combination of SLIF positive responses can be a predictor of non-physiological respiratory pattern changes in people with CLBP. Clinically, this prediction is expected to help save time for screening and improve the efficiency of therapy.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.1
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• pp.1-17
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• 2019

The importance of education in formulating and complementing climate change response has been widely recognized by international and national frameworks, agendas, strategies and action plans. Climate change education has the potential to meet the needs of communities to access updated information and knowledge on climate change, supporting policy development and the enhancing effectiveness of climate change response. This study develops an innovative model of Integrated Urban Climate Education (IUCE) as one suitable method for teaching and learning climate change and urbanization. This paper presents approaches, methodology and key lessons learned from the case study of IUCE in Cam Le District of Da Nang City. Findings from the study identify a number of important characteristics about the development and implementation of IUCE in a way that effectively contributes to urban resilience building. These characteristics include (1) multidimensional approaches, (2) teacher - centered base, (3) school-family-community connection, and (4) symbiosis principle.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.6
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• pp.49-54
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• 2020

The purpose of this study is to investigate the effects of the change in the spindle speed and the feed rate on the diameter change of a hole using a boring cutter for the internal boring process of AL6061-T4 alloys. The experimental results are quantitatively analyzed by applying the factor analysis and the response surface analysis of the experimental design method. The tendency of the diameter change according to the change in the spindle speed and feed level is also evaluated. During the internal boring process of AL6061-T4 alloys, the main factor affecting the diameter change is the spindle speed in which the diameter decreases as the number of revolutions increases. In addition, the diameter tends to increase as the feed is increased; however, as the number of spindle revolutions increases, the influence of the feed decreases.

• Proceedings of the Korean Society for Quality Management Conference
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• 2010.04a
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• pp.474-482
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• 2010

The Research of local governments in addressing climate change policy formulation and enforcement role in the formulation of local governments, and faithful to the role of local governments when addressing climate change to policy issues and is aimed to provide direction. The role of local governments' Star Statement by looking at best practices, through which more realistic and effective climate change response measures would be able to set aside. Local party organizations in addressing climate change and understanding the role and establishment and enforcement of the policy must be balanced community and residents more comfortable and be able to provide a comfortable life.