• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.3
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• pp.230-238
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• 2003

In this paper, Inverter drives adopting 2 phase space vector SRP-PWM (Separately Randomized Pulse Position PWM) with fixed switching frequency is proposed. The proposed 2 phase space vector SRP-PWM scheme is based on the 3 phase SRP-PWM. In the proposed SRP-PWM scheme, each of two phase pulses is located randomly in each switching interval. The experimental results show that the voltage and acoustic noise harmonics are spread to a wide band area. Also, the performance of the proposed 2 phase SRP-PWM and the conventional center aligned SVM are compared to each other. In result, the speed response is nearly similar to each other from the viewpoint of the v/f constant control.

• Journal of Pharmacopuncture
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• v.21 no.1
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• pp.7-13
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• 2018

Objective: Hwa-byung is one of the cultural concept of distress in Korea resulted from chronic accumulated anger. It is characterized by various symptoms like stuffy in the chest, hot or heat sensation, something pushing up in the chest, feeling of mortification, and a flush of anger. This protocol aims to explore the efficacy and safety of Huanglian-jie-du decoction on various somatic symptoms and insomnia in patients with Hwa-byung. Methods: This is study protocol for a randomized, double-blind, placebo-controlled trial. A total of 44 patients will be randomly assigned to the experimental group or the placebo group in a 1:1 ratio. All medications will be taken orally 3 times per day for 7 consecutive days. The primary outcomes are the mean changes in Patient Health Questionnaire of physical symptoms (PHQ-15) and Insomnia Severity Index (ISI) after the 7 days of administration. The secondary outcomes include the scales to assess stress response, symptoms of Hwa-byung, and state anger. Conclusion: The results of this study will provide high quality and explorative evidence to investigate the effect of Huanglian-jie-du decoction on Hwa-byung.

• Journal of People, Plants, and Environment
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• v.23 no.2
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• pp.125-138
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• 2020

The aim of this study was to review previous literature to determine the effects of nature-based program for workers. This systematic review was conducted in accordance with National Evidence-based Healthcare Collaborating Agency's guidance for undertaking systematic reviews for intervention. Literature search was performed using National Assembly Digital Library, Korean Studies Information Service System, and Korea Education & Research Information Service for literature published until March 2019. The participants were full-time workers, and intervention of nature-based programs was conducted in the outdoor, indoor, and indirect nature contact exposures, with comparators in the control group who did not receive the treatment. The results showed that the programs were effective in physical, psychological, and social health. The methodological quality of randomized controlled trials (RCT) was assessed using the Cochrane Risk of Bias(RoB) tool, while non-randomized controlled trials (N-RCT) were assessed using the Cochrane Risk of bias assessment tool for non-randomized studuies (RoBANS). A total of 16 studies were selected for assessment: two RCTs, 10 N-RCTs, and four one-group pretest-posttest designs. Most interventions were provided at the workplace and in the community. There were many kinds of nature-based interventions, and forest therapy and horticultural therapy programs were most common. Various interventions for workers effectively improved job stress, depression, serum cortisol and stress-response. However, the included studies lacked methodological rigor. Future research is needed to evaluate the long-term effectiveness of nature-based programs for workers using rigorous research designs.

• Journal of the Korean Statistical Society
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• v.25 no.1
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• pp.39-48
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• 1996

A new method that uses information obtained not only from randomization device but also from direct question is introduced. The new maximum likelihood estimator is compared with those of Warner(1965) and Mangat(l994). For a choice of randomized device, we propose a choice depending on the sample size n and show that our estimator is more efficient than that of Mangat under the randomization device. The proposed procedure is extended to more general one which can be easily applied to some specific cases. Under the specified conditions, it is shown that the variance of this generalized estimator is smaller than that of Warner.

• Journal of Veterinary Clinics
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• v.31 no.4
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• pp.288-292
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• 2014

A critical assumption of the standard sample size calculation is that the response (outcome) for an individual patient is completely independent to that for any other patient. However, this assumption no longer holds when there is a lack of statistical independence across subjects seen in cluster randomized designs. In this setting, patients within a cluster are more likely to respond in a similar manner; patient outcomes may correlate strongly within clusters. Thus, direct use of standard sample size formulae for cluster design, ignoring the clustering effect, may result in sample size that are too small, resulting in a study that is under-powered for detecting the desired level of difference between groups. This paper revisit worked examples for sample size calculation provided in a previous paper using nomogram to easy to access. Then we present the concept of cluster design illustrated with worked examples, and introduce design effect that is a factor to inflate the standard sample size estimates.

• The Korean Journal of Applied Statistics
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• v.6 no.2
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• pp.311-318
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• 1993

In this paper, we consider the test based on using Forced question model instead of Warner model and compare the power of two randomized respose models. The estimator for the prportion of the individuals belonging to the sensitive group is obtained by using Forced question model and the conditions that the estimator by Forced question model will be more efficient than the estimators by Warner model are found when the respondents are truthrul in their answers.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2095-2100
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• 2014

Objective: Most patients with advanced breast cancer experience resistance to endocrine treatment and eventual disease progression. This meta-analysis was designed to compare the efficacy and tolerability of fulvestrant 250mg with anastrozole 1mg in postmenopausal women with advanced breast cancer. Methods: Electronic literature databases (Cochrane Library, Medline, and Embase) were searched for randomized controlled trials (RCTs) published prior to August 2013. Only RCTs that compared fulvestrant 250mg to anastrozole 1mg in postmenopausal women with advanced breast cancer were selected. The main outcomes were time to treatment failure (TTF), time to progression (TTP), duration of response (DOR), clinical benefit rate, and tolerability. Results: Four RCTs covering 1,226 patients (fulvestrant, n=621; anastrozole, n=605) were included in the meta-analysis. Fulvestrant increased the DOR compared to anastrozole (HR =1.31, 95% confidence interval [CI] 1.13-1.51). There was no statistically significant difference between fulvestrant and anastrozole in terms of TTF (HR=1.02, 95%CI 0.89-1.17), complete response (RR=1.79, 95%CI, 0.93-3.43), and partial response (RR=0.91, 95%CI 0.69-1.21). As for safety, there was no statistical significance between the two groups for common adverse events. Conclusion: Fulvestrant 250mg is as effective and well-tolerated as anastrozole 1mg treatment for advanced breast cancer in postmenopausal women whose disease progressed after prior endocrine treatment. Thus, fulvestrant may serve as a reasonable alternative to anastrozole when resistance is experienced in breast cancer cases.

• Physical Therapy Rehabilitation Science
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• v.9 no.4
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• pp.309-317
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• 2020

Objective: One of the treatment strategies for controlling chronic pain and preventing disability is patient education. Pain neuroscience education (PNE) has been proven to be effective in explaining the biological and physiological processes associated with pain experiences to patients. The purpose of this review is to investigate the effectiveness of PNE for kinesiophobia such as avoidance response in patients with chronic pain. Design: A systematic review and meta-analysis. Methods: MEDLINE, EMBASE, CINAHL, PEDro, and the Cochrane Central Register of controlled trials databases were searched through November 2020 and included a randomized controlled trials evaluating kinesiophobia in musculoskeletal patients with chronic pain. In 8 randomized controlled trial studies, 'Cochrane's risk of bias (RoB) tool was used for qualitative analysis, and results of post-intervention were analyzed through RevMan 5.4 for quantitative analysis. Results: For this review, 8 randomized controlled trials of 369 patients with chronic pain were selected for PNE. A systematic review and meta-analysis also included 8 randomized controlled trials. The effect on kinesiophobia was more effective than the control group (-0.86; 95% confidence interval [CI], -1.22 to -0.51; heterogeneity [χ²=21.18, df=7, I²=67%]; overall effect [Z=4.80]). In addition, the effect on pain was more effective than the control group (-0.53; 95% CI, -1.05 to -0.01; heterogeneity [χ²=47.42, df=7, I²=85%]; overall effect [Z=2.01]). Conclusions: The results of this review suggest that PNE and combined PNE have a positive effect on the improvement of pain and kinesiophobia in patients with chronic pain.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1023-1028
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• 2004

A micro-pressure wave is generated by the high-speed train which enters a tunnel, and it causes explosive noise and vibration at the exit. It is known that train speed, train-tunnel area ratio, nose slenderness and nose shape mainly influence on generating micro-pressure wave. So it is required to minimize it by searching optimal values of such train shape factors and tunnel condition. In this study, response surface model, one of approximation models, is used to perform optimization effectively and analyze sensitivity of design variables. Owen's randomized orthogonal array and D-optimal Design are used to construct response surface model. In order to increase accuracy of model, stepwise regression is selected. Finally SQP(Sequential Quadratic Programming) optimization algorithm is used to minimize the maximum micro-pressure wave by using built approximation model.

• Nutrition Research and Practice
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• v.12 no.5
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• pp.371-377
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• 2018

BACKGROUND/OBJECTIVES: Elevation of postprandial lipemia characterized by a rise in triglyceride (TG)-rich lipoproteins can increase the risk of atherogenesis. The objective of this study was to investigate postprandial lipemia response to a single dietary fat/sugar load test and monitor beneficial changes induced by the consumption of Platycodi radix (AP) beverage in healthy subjects. SUBJECTS/METHODS: A total of 52 subjects were randomly assigned to either placebo or AP beverage group with a high-fat shake in a randomized controlled crossover trial. Postprandial blood was collected at 0, 1, 2, 4, and 6 h and analyzed for TG and lipoprotein lipase mass. Inhibition of pancreatic lipase was determined in vitro. RESULTS: AP inhibited pancreatic lipase activity in vitro ($IC_{50}=5mg/mL$). Compared to placebo beverage, AP beverage consumption with a high-fat shake induced significant increase of plasma lipoprotein lipase mass (P = 0.0111, ${\beta}$ estimate = 4.2948) with significant reduction in very low-density lipoprotein (VLDL) TG concentration (P = 0.038, ${\beta}$ estimate = -52.69) at 6 h. Based on significant correlation between high-fat dietary scores MEDFICTS and postprandial TG responses in VLDL (P = 0.0395, r = 0.2127), subgroup analysis revealed that 6 h-postprandial VLDL TG response was significantly decreased by AP consumption in subjects with MEDFICTS ${\geq}40$ (P = 0.0291, ${\beta}$ estimate = -7214). CONCLUSIONS: AP beverage might have potential to alleviate postprandial lipemia through inhibiting pancreatic lipase activity and elevating lipoprotein lipase mass. Subgroup analysis revealed that subjects with high-fat dietary pattern could be classified as responders to AP beverage among all subjects.