• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.E
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• pp.67-73
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• 1990

Many distress mechanisms in pavement are known to be caused by the poor mechanical properties of bituminous concretes. Among many mechanical properties, tensile strength is one of the more important indicates that represent the resistance of pavement to traffic loading. However, there has been no relationship established between the strength and distress mechanisms. Therefore, this study was conducted to evaluate a correlation between the tensile strength value and the intensity of distress in bituminous concrete. Distress data were collected from an extensive field investigation over 77km of a four-lane highway in South Carolina, USA, and from laboratory prepared specimens in two phases of study. Strength data were obtained from a total of more than 400 field cores taken from the same highway and from 640marshall specimens of surface course mixture prepared in the laboratory. These data were analyzed using statistical test techniques. It was found from statistical analyses that the tensile strength of bituminous concrete had a strong relation with the pavement condition in the field. In the analysis of rutting and stripping, low strength concrete showed a higher distress rate in the mixture, and mixtures under distress in the field showed obviously reduced strength values. Stripping was found to be the most significant distress mechanism that was correlated with low strength bituminous concrete. Rutting appeared more frequently in a low strength pavement section of the highway as a sign of failure due to traffic loading.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.316-321
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• 2007

This paper is proposed a novel method to approximate the maximum power for a photovoltaic inverter system and tracking method. It is designed for power systems application and utilities. The proposed Maximum Power Point Tracking(MPPT) control has the advantage to provide a new simple way to approximate the optimal or rated voltage, the optimal or rated current and maximum power rating produced by a solar panel and the photovoltaic inverter. And this straightforward method will be named linear reoriented coordinates method(LRCM) with the advantage that Pmax and $V_{op}$ can be approximated using the satre variable as the dynamic model without using complicate approximations or Taylor series. Furthermore tracking method is improved over 50% photovoltaic efficiency. This paper is proposed MPPT using LRMC and tracking method using weather condition of domestic moderate program technique. This paper is proposed the experimental results to verify the effectiveness of the new methods.

• Journal of Oral Medicine and Pain
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• v.41 no.4
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• pp.188-194
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• 2016

Purpose: Burning mouth syndrome (BMS) is ambiguous and enigmatic oral condition. Sleep disturbance is one of the most prevalent complaints of patients with chronic pain. The aim of this study was to estimate general sleep characteristics and propensity in patients with BMS. Methods: A total of thirty BMS patients and thirty healthy control subjects were investigated. Self-reported measures of sleep quality were conducted using two widely used methods; the Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). Data were analyzed with one-way ANOVA, chi-square, Fisher's exact test, Kruskal-Wallis test, Holm method with 95% confidence interval and p<0.05 significant level. Results: BMS patients showed more poor sleepers than those in control subjects in both ESS and PSQI test. BMS patients also showed statistically significant poorer sleep quality compared with control subjects in both test. When BMS group were divided into three groups on the basis of numeric rating scale, the higher score subjects had, the more mean rank they had in the PSQI. Conclusions: BMS patients showed up poor sleep characteristics and propensity than control group, and they also showed the more severe the pain was, the worse the sleep quality was.

• Journal of the Korea Safety Management & Science
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• v.16 no.3
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• pp.267-271
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• 2014

The objectives of this study were to evaluate the safe criteria of portable slipmeter using human perception onto the several different floor surfaces under contaminated conditions. It was difficult to find why many different slipmeters took there's own safe criteria. It is still unclear how thres hold values established in many literatures. Two different subjective slippery evaluating methods, AHP(Analytic Hierarchy Process) and Friedman test,were used to evaluate the perception of slipperiness of seven different floor surfaces under the contaminated condition with detergent solution. Twelve subjects worn same footwear and walked with self-selected step and cadence along the test floors. The SCOF(Static Coefficient of Friction) obtained for same test conditions with BOT-3000 was compared to perception of slipperiness to establish as a safe criteria. The very high significant correlation(r=0.97) was found between AHP and Friedman test. Also, The high significant correlation(r=0.96) was found between AHP and SCOF obtained with BOT-3000. The results suggested that the SCOF should be greater than 0.63 for safer walking. Perception rating obtained with AHP showed a high correlation with Friedman test and the SCOF obtained with BOT-3000 except for polished tile floor. The safe criteria obtained through this study were similar to ANSI/NFSIB101.1.

• Journal of the Ergonomics Society of Korea
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• v.26 no.4
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• pp.49-56
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• 2007

Handles on objects are very important to increase the safety and efficiency of manual handling of people who use them. In this study, four different prototype cartons combined with auxiliary handles were designed to determine the optimal handle position of cartons through the evaluation of user preferences. Twenty male students are participated in the experiment. Likert-5 point summated rating method was applied to evaluate the user preferences for provided handles of the carton among upper, middle, and lower position under the four different sizes and materials handling conditions(carrying positions). The results show that the subjects preferred upper part of the handle on the small cartons regardless of the carrying positions while upper and middle parts of the handle on the big cartons for handling above the waist height were preferred. An optimal handle position depending on the different sizes of carton and the different carrying positions were recommended based on the results of evaluation. It is thus recommended that the cartons provide handles on its relevant position depending on the size and materials handling condition to reduce the musculoskeletal stress and in turn to increase the user satisfaction.

• The Journal of Internal Korean Medicine
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• v.40 no.6
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• pp.1210-1218
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• 2019

Objective: This study is a report on a case of a Guillain-Barre syndrome patient with quadriplegia and paresthesia, whose condition was improved by Korean medicine treatment. Methods: A 71-year-old woman diagnosed with Guillain-Barre Syndrome was treated by acupuncture, electroacupuncture, Sambi-tang-gami, cupping, moxibustion, and rehabilitation. Clinical symptoms were measured with the Manual Muscle Test (MMT), the Numeric Rating Scale (NRS), the Modified Barthel Index (MBI), and the Functional Independence Measurement (FIM). Result: After treatment, clinical symptoms showed improvement. Conclusion: Korean medicine treatment could be effective in the treatment of Guillain-Barre syndrome patients with quadriplegia and paresthesia.

• Journal of TMJ Balancing Medicine
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• v.9 no.1
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• pp.18-23
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• 2019

Objectives: The aim of our study was to report clinical improvement of a patient who suffered from Temporomandibular Disorder (TMD) being treated with Korean Medical treatments and Intraoral Balancing Appliance (IBA). Methods: During the admission period, the patient was treated with acupuncture, cupping, Korean Medicine, Chuna therapy and FCST (Functional Cerebrospinal Therapy) every day. And we observed patient's condition by Numeric Rating Scale (NRS), Pain Disability Index (PDI), EQ-5D-5L (Five-level EuroQol-5 dimensions), and assessment about range of motion(ROM) for temporomandibular joint and cervix. Results: After treated for 4 weeks, the patient's NRS, PDI, EQ-5D-5L and ROM were improved. Conclusions: Korean Medical treatments including FCST are estimated to be effective for patients with TMD. But the case was only one, so more cases and further research is needed to prove the effectiveness of the treatment.

• Journal of Korean Academy of Nursing
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• v.30 no.3
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• pp.709-719
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• 2000

The purposes of the study was to identify the depression of women after a hysterectomy and to clarify the factors related to depression. This was a cross-sectional descriptive study. The data was collected by a mailed questionnaire that was composed of the Zung Self-Rating Depression Scale(SDS), support scale of husband and socio-demographic variables from 255 women undergoing hysterectomies for any nonmalignant condition in S. University Hospital. They also must have lived with their spouses from 3 months to 2 years after the operation. The results were as follows: 1. The SDS mean was 42.25 and range was 21 to 67. The incidence of clinical depression (over SDS 50) was 20.8% from 3 months to 2 years after a hysterectomy. 2. The depression of women in 18-24 months after surgery (39.80) was lower than that of any other periods such as 3-5 months, 6-12 months, and 13-17 months (p<0.01). 3. The support form husband was negatively correlated with the depression of women after a hysterectomy. 4. Depression among women tho had hysterectomies were associated with lower income, less sexual satisfaction, the feeling of being asexual, and the bias of concept the uterus controlling general health.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.587-588
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• 2010

The maximum output torque developed by the machine is dependent on the allowable current rating and maximum voltage that the inverter can supply to the machine. Therefore, to use the inverter capacity fully, it is desirable to use the control scheme considering the voltage and current limit condition, which can yield the maximum torque per ampere over the entire speed range. This controller is controlled speed using artificial intelligent PI(AIPI) controller. Also, this paper is proposed control of maximum torque per ampere(MTPA) of induction motor. The performance of the proposed induction motor drive with maximum torque control using AIPI controller is verified by analysis results at dynamic operation conditions.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.231-236
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• 2003

HCCI(Homogeneous Charge Compression Ignition) combustion is an advanced combustion process explained as a homogeneously premixed charge of a fuel where air is admitted into the cylinder and compression ignited. It has possibility to reduce NOx by spontaneous auto-ignition at multiple points that allows very lean combustion resulting in low combustion temperatures. Particulate matters (PM) could be also reduced by the homogeneous combustion and no fuel-rich zones. Injection timing is extremely advanced to achieve homogeneous charge where a diesel fuel could not be vaporized sufficiently due to low pressure and low temperature condition. Also the over-penetration could be a severe problem. The small injection angle and multi-hole injectors were applied to solve these problems. Dimethyl ether (DME) as an altenative fuel was also applied to relive the bad vaporization problem associated with early injection of diesel fuel. Neat DME has a very high cetane rating and high vapor pressure. Contained oxygen reduces soot during the combustion. Experimental result shows DME can be easily operated in an HCCI engine. PM shows almost zero value and NOx is reduced more than 90% compared to direct-injection diesel engine operating mode but problem of early ignition needs more investigation.