• Journal of the Korean Society for Precision Engineering
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• v.33 no.7
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• pp.551-558
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• 2016

Reduction of welding residual stress is very important in the railway industry, but calculating its distribution in structures is difficult because welding residual stress formation is influenced by various parameters. In this study, we developed a finite element model for simulating the repair welding process to recover a surface damaged rail, and conducted a series of parametric studies while varying the cooling rate and the duration of post weld heat treatment (PWHT) to find the best conditions for reducing welding residual stress level. This paper presents a three-dimensional model of the repair welding process considering the phase transformation effect implemented by the ABAQUS user subroutine, and the results of parametric studies with various cooling rates and PWHT durations. We found that heat treatment significantly reduced the residual stress on the upper rail by about 170 MPa.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.270-279
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• 2009

During the course of a study to develop a spraying program at 15-day spray intervals, two important findings were identified allowing for further reduction of spray frequency by increasing the spray interval. In evaluating the contribution of fungicides from a 15-day spray interval program, control of white rot, which is of prime importance in Korea, was not affected, in spite of the extended spray interval caused by omitting the fungicides during the season. In another experiment assessing the duration of the protective activities of several key fungicides used in the 15-day spray interval program, infection control was maintained for almost 30 days for some fungicide. Based on these two findings, a basic spraying program with a 25-day spray interval was developed. This program was modified for four successive years to improve the control efficacy against bitter rot and Marssonina blotch, which sometimes causes as much damage as white rot.

• Journal of Korean Foot and Ankle Society
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• v.11 no.2
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• pp.149-153
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• 2007

Purpose: To evaluate the possible risk factors of lower extremity amputations in diabetic foot patients. Materials and Methods: The study is based on 37 patients who received lower extremity amputations from April, 1997 to February 2005 due to diabetic foot complications with at least 1 year follow up. As for the control group, 49 diabetes patients who had been treated at the endocrinology department for at least 1 year without any diabetic foot complication were evaluated. As for the possible risk factors, age, gender, duration of diabetes mellitus, body mass index, Hb A1c, blood glucose level, total cholesterol, s-creatinine, C-peptide, smoking, alcohol, hypertension, cardiovascular disease, CVA, retinopathy and neuropathy were investigated. Results: Among the possible risk factors evaluated, age, Hb A1c, smoking, neuropathy and blood glucose level factors showed statistically significant difference between the diabetic amputation and the control group. Conclusion: In reducing the risk of the lower extremity amputations in the diabetic patients due to diabetic foot complications, strict control of blood glucose level and cessation of smoking were found to be utmost important.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.3
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• pp.256-263
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• 2009

The operating range of HCCI engine is narrow due to excessive rate of pressure rise on high load. The fuel stratification is proposed to solve the problem. The purpose of this study is to gain a better understanding of the effects of fuel stratification on reducing the pressure-rise rate at high load in HCCI combustion and to investigate that the operating range is expanded for fuel stratification in the preceding condition of initial temperature and equivalence ratios. The engine is fueled with Di-Methyl Ether (DME) which has unique 2-stage heat release. The computations were conducted using SENKIN application of the CHEMKINll kinetics rate code. Calculation result shows that proper fuel stratification prolongs combustion duration and reduce pressure rise rate.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.2
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• pp.710-726
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• 2018

This paper presents an extended particle filter to increase the accuracy and decrease the computation load of vehicle tracking. Particle filter has been the subject of extensive interest in video-based tracking which is capable of solving nonlinear and non-Gaussian problems. However, there still exist problems such as preventing unnecessary particle consumption, reducing the computational burden, and increasing the accuracy. We aim to increase the accuracy without an increase in computation load. In proposed method, we calculate the direction angle of the target vehicle. The angular difference between the direction of the target vehicle and each particle of the particle filter is observed. Particles are filtered and weighted, based on their angular difference. Particles with angular difference greater than a threshold is eliminated and the remaining are stored with greater weights in order to increase their probability for state estimation. Threshold value is very critical for performance. Thus, instead of having a constant threshold value, proposed algorithm updates it online. The first advantage of our algorithm is that it prevents the system from failures caused by insufficient amount of particles. Second advantage is to reduce the risk of using unnecessary number of particles in tracking which causes computation load. Proposed algorithm is compared against camshift, direction-based particle filter and condensation algorithms. Results show that the proposed algorithm outperforms the other methods in terms of accuracy, tracking duration and particle consumption.

• Journal of Pharmacopuncture
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• v.8 no.1
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• pp.5-11
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• 2005

Objectives : This study has been designed and performed to identify the effect of Hominis Placenta herbal acupuncture which is usually used in reducing sleep pattern disturbances. Methods : The study subjects studied included 48 patients who were admitted in hospital located in Pusan, and they were classified into 2 groups : 25 patients in the experimental group who injected Hominis Placenta herbal acupuncture and 23 patients in the control group who were treated by acupuncture. The both group injected on $GB_{20}$, $GB_{12}$ and $GB_{20}$ for 5 days without medicine. The sleep pattern disturbance score was measured by using 15 questions according to Korean Sleep Scale A(Oh, Jin Joo. Song, Mi. Soon. Kim, Shin Mi. 1998). Results & conclusions : The sleep pattern disturbance score of the experimental group who injected Hominis Placenta herbal acupuncture was significantly lower than that of the control group(t=7.00 p=.00). These results provided that Hominis Placenta herbal acupuncture of $GB_{20}$, $GB_{12}$ and HT, was effective for relieving sleep pattern disturbances, it is need mere sample's number and more treatment's duration.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.1
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• pp.21-32
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• 1997

Optimum design of water distribution network(WDN) in many times means just reducing redundancy. Given only a few situations are taken into consideration for such design, WDN deprived of inherited redundancy may not work properly in some unconsidered cases. Quantifying redundancy and incorporating it into the optimal design process will be a way of overcoming just reduction of redundancy. Expected shortage is developed as a reliability surrogate in WDN. It is an indicator of the frequency, duration and severity of failure. Using this surrogate, Expected Shortage Optimization Model (ESOM) is developed. ESOM is tested with an example network and results are analyzed and compared with those from other reliability models. The analysis results indicate that expected shortage is a quantitative surrogate measure, especially, good in comparing different designs and obtaining tradeoff between cost and. reliability. In addition, compared other models, ESOM is also proved useful in optimizing WDN with reliability and powerful in controlling reliability directly in the optimization process, even if computational burden is high. Future studies are suggested which focus on how to increase applicability and flexibility of ESOM.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.315-321
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• 1994

The addition of green tea to kimchi making for extanding the optimum edible period was studied. The equality and sensory characteristics of green tea added kimchi were evaluated. The acidity, lactic acid and acetic acid contents of green tea added kimchi showed lower than that of control kimchi but reducing sugar and vitamin C contents was higher. The duration of optimum edible periods of green tea added kimchi lasted two more weeks. While the optimum pH of kimchi for eating lasted, the sensory pannel score for sour taste of green tea added kimchi was lower than that of control but the scores for overall quality and hardness were higher. Especially, the sour taste score between two groups were significantly different(p<0.05). There was no differences in texture determined by Penetrometer between green tea added kimchi and control kimchi until the fermentation reached the optimal condition for eating. After that period, the degree of degradation of texture was much delayed in green tea added kimchi.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.3
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• pp.19-25
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• 2010

The purpose of this study is to gain a better understanding of the effects of fuel stratification on reducing the pressure-rise rate at high load in HCCI combustion. It was found that fuel stratification offers good potential to achieve a staged combustion event and reduced pressure-rise rates. The engine is fueled with Di-Methyl Ether (DME) which has unique 2-stage heat release. Numerical analysis is conducted with single and multi-zones model and detailed chemical reaction scheme is done by chemkin and senkin. Calculation result shows that proper fuel stratification prolongs combustion duration and reduce pressure rise rate. Besides IMEP, combustion efficiency and indicated thermal efficiency keep constant. However, too wide fuel stratification increases pressure rise rate and CO and NOx emissions in exhaust gas.

• The Korean Journal of Pain
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• v.26 no.3
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• pp.242-248
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• 2013

Varicella (chickenpox) is a highly contagious airborne disease caused by primary infection with the varicella zoster virus (VZV). Following the resolution of chickenpox, the virus can remain dormant in the dorsal sensory and cranial ganglion for decades. Shingles (herpes zoster [HZ]) is a neurocutaneous disease caused by reactivation of latent VZV and may progress to postherpetic neuralgia (PHN), which is characterized by dermatomal pain persisting for more than 120 days after the onset of HZ rash, or "well-established PHN", which persist for more than 180 days. Vaccination with an attenuated form of VZV activates specific T-cell production, thereby avoiding viral reactivation and development of HZ. It has been demonstrated to reduce the occurrence by approximately 50-70%, the duration of pain of HZ, and the frequency of subsequent PHN in individuals aged ${\geq}50$ years in clinical studies. However, it has not proved efficacious in preventing repeat episodes of HZ and reducing the severity of PHN, nor has its long-term efficacy been demonstrated. The most frequent adverse reactions reported for HZ vaccination were injection site pain and/or swelling and headache. In addition, it should not be administrated to children, pregnant women, and immunocompromised persons or those allergic to neomycin or any component of the vaccine.