• Journal of Chest Surgery
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• v.30 no.1
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• pp.1-10
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• 1997

The successful cardiac transplantation depends partly on the donor heart preservation by a solution that will ensure recovery of myocardial function. The purpose of this study was to perform the evaluation of various preservation solutions and to accumulate the data on the requisites for ideal preservation solution. The experimental setup was the constant pressure Langendorffs perfusion system. Isolated rabbit hearts were perfused for 20minutes with unarm Krebs-Henseleit solution, stored for 4 hours in cold preservation solution after cardioplegia, and then were reperfused for 20minutes. The 4 experimental groups were prepared Hartmann's solution group (group 1, control), modified Euro-collins solution group(group II. MEC), modified University of Wisconsin group (group n, MUW), and CK solution(made by the author) group (group W, CK). The parameters for assessing the preservation ability were levels of enzymes in freezed myocardial tissues (lactate, creatine kinase-MB and adenosine deaminase), coronary flow. left ventricular developing pressure and dpldt. In conclusion, the ability of preservation for isolated rabbit heart was excellent in CK solution and modified University of Wisconsin solution, and poor in modified Euro-collins solution, compared with Hartmann solution. CK solution has low potassium concentrations(34.2mEq/L) and includes various substrates to be salutary on myocardial preservation. This fact may indicates the necessity of further refinements in selection or composition of electrolytes and substrates.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.5
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• pp.118-124
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• 2011

To reach the Euro-6 regulations of PM and $NO_x$ for light-duty diesel vehicles, it will be necessary to apply the CDPF and the de-$NO_x$ catalyst. The described system consists of a catalytic configuration, where the CDPF is placed downstream of the diesel engine and followed by a urea injection unit and a urea-SCR catalyst. One of the advantages of this system configuration is that, in this way, the SCR catalyst is protected from PM, and both white PM and deposits become reduced. In the urea-SCR system, the injection control of reductant is the most important thing in order to have good performance of $NO_x$ reduction. The ideal ratio of $NH_3$ molecules to $NO_x$ molecules is 1:1 based on $NH_3$ consumption and having $NH_3$ available for reaction of all of the exhaust $NO_x$. However, under the too low and too high temperature condition, the $NO_x$ reduction efficiency become slower, due to temperature window of SCR catalyst. And space velocity also affects to $NO_x$ conversion efficiency. In this paper, rig-tests were performed to evaluate the effects of $NO_x$ and $NH_3$ concentrations, gas temperature and space velocity on the $NO_x$ conversion efficiency of the urea-SCR system. And vehicle test was performed to verify control strategy of reductatnt injection. The developed control strategy of reductant injection was improved over all $NO_x$ reduction efficiency and $NH_3$ consumption in urea-SCR system. Results of this paper contribute to develop urea-SCR system for light-duty vehicles to meet Euro-5 emission regulations.

• Journal of Chest Surgery
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• v.30 no.11
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• pp.1055-1061
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• 1997

In the field of the experimental lung transplantation, we analyzed the CT findings of acute rejection, infection in the left single allotransplanted lung of adult mongrel dogs, and the CT findings were compared with the histological findings obtained by the lung biopsy Twenty two adult mongrel dogs were divided into two groups(Donor and recipient group). Donor lungs were flushed with LPDG(low pota,ilium dextral glucose) solution(n=4) or modified Euro-collins solution(n=7) and preserved over 20 hours with $10^{\circ}C(1$ case preservation for 4hours). After left single lung transplantation, the chest X-ray and sequential computed tomogram were performed with concomitant hemodynamic study and arterial blood gas analysis on immediate postoperative period, postoperative 3rd day and postoperative 7th day. Two of eleven transplanted lungs had acute rejection which was represented as moderate infiltration at immediate or 1st postoperative d y but became extensive infiltration at postoperative 3rd day on CT. There were showed one case of bronchopleural fistula, six cases of pneumonia and two cases of pulmonary infarction. In one rejection cases, the opacity of transplanted lung was improved by injection of methylprednisolone 500mg daily during 3 days. We concluded that CT was a useful noninvasive evaluation parameter after lung transplantation and the serial CT scan enabled early detection of acute rejection.

• The Journal of the Korea Contents Association
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• v.15 no.2
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• pp.363-369
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• 2015

Chronic pain is one of the leading causes of hospital visits. It not only affects the patients themselves but also has a major negative impact on their families and society. In this study, we investigated epidemiology of musculoskeletal disorders induced chronic pain among general population based on Korea National Health and Nutrition Examination Survey database and also analysed how it influenced on the use of medical services. This study was done by using the data of 5th Korea National Health and Nutrition Examination Survey (KNHANES V), taking aged 20 years and over adults as research subjects. The EuroQoL-5 Dimension Index(EQ-5D) was used as a survey instrument. T-test, chi-square test and multivariate logistic regression were used for statistical analysis. Subjects with chronic pain had a higher likelihood than control group to use medical services(odds ratio : 5.858, confidence interval 3.636-9.438). Controlling for existence of chronic pain, more women were likely to use medical services than men(1.156, 0.707-1.889). Age, gender and household income level did not affect the use of medical services. Proper control of chronic pain is very helpful in improving patient's quality of life and it also accounts for a large proportion in suppressing excessive consumption of medical services. Anesthesia and pain medicine specialists have superior knowledge about analgesics and anticonvulsants than other physicians do and also have specialized skills to perform procedures like nerve blocks in treating chronic pain. Therefore Anesthesia and pain medicine specialists need to play a leading role in managing chronic pain.

• Journal of the Korea Concrete Institute
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• v.17 no.6 s.90
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• pp.955-962
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• 2005

Still no accurate theory exists for predicting ultimate shear strength of deep reinforced concrete beams because of the structural and material non-linearity after cracking. Currently, the load capacity assesment is performed for the upper structure of the bridges and containing non-reliability in the applications and results. The purpose in this study is to evaluate analytically the complex shear behaviors and normal strength for the reinforced concrete deep beams and to offer the accuracy load capacity assesment method based on the reliability theories. This paper presents a method for the load capacity assesment of reinforcement concrete deep beams using nonlinear finite element analysis. A computer program named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures was used. Material non-linearity is taken Into account by comprising tensile, compressive and shear models of cracked concrete and a model of reinforcing steel. From the results, determine the reliability index for the failure base on the Euro Code. Then, calculate additional reduction coefficient to satisfy the goals from the reliability analysis. The proposed numerical method for the load capacity assesment of reinforced concrete deep beams is verified by comparison with the others methods.

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1349-1360
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• 2016

The purpose of this study was to identify the degree of quality of life (QoL) and its related factors in patients with Korean Chronic Obstructive Pulmonary Disease (COPD). With data collected by Korea National Health and Nutrition Survey in 2013, general and disease-related variables, pulmonary function test, and EuroQol-5Dimension (EQ-5D) were analyzed. The mean of EQ-5D index was 0.916 in patients with COPD and 0.941 in non-COPD. The EQ-5D index and its sub dimensions (mobility, self-care, usual activity, pain/discomfort, anxiety/depression) of COPD patients were significantly lower than that of non-COPD. However, difference in COPD patients' airway limitation was significant only for self-care of EQ-5D (${\chi}^2=9.50$, p=.013). The related factors of QoL in COPD patients were age, gender, level of education, quartile of household income, smoking status, and number of comorbid diseases. Based on the results, it is important to pay close attention to COPD patients' QoL as well as comprehensive interventions which possibly improve their QoL.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.762-767
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• 2016

High thermal efficiency and the ability to use various types of fuel are a few of the many advantages of diesel engines. However, a major disadvantage is that their exhaust emissions are more harmful to humans and the environment than that of conventional engine. Consequently, the provisions of the international emissions standards for diesel engine equipped passenger cars, commercial vehicles, and ships have become more stringent. These standards include the EU Euro 6, the IMO MEPC Tier 3, and the US EPA Tier 4. Ryu et al. published a study that applied fuel additives to two-stroke diesel engines. In this study, a four-stroke diesel engine using diesel oil for a generator is utilized as the test subject, and an experiment is performed to verify whether fuel additive can be used to improve performance and exhaust emissions. In addition, this experimental study presents research results for the application of fuel additives in both two-stroke and four-stroke diesel engines. The experimental results were compared and analyzed by placing an oil-soluble calcium-based organometallic compound in diesel oil. The results confirmed that the addition of fuel additive improved the performance (fuel consumption rate, exhaust gas temperature) and exhaust emissions (NOx, CO) of the diesel engine.

• The Korean Journal of Financial Management
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• v.26 no.2
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• pp.155-180
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• 2009

This study is to estimate and compare hedging effectiveness in emerging currency and advanced currency futures markets. Emerging currency futures includes Korea won, Mexico peso, and Brazil real and advanced currency futures is Europe euro, British pound, and Japan yen. Hedging effectiveness is measured by comparing hedging performance of the naive hedge model, OLS model, error correction model and constant condintional correlation bivariate GARCH(1, 1) hedge model based on rolling windows. Analysis data is used daily spot and futures rates from January, 2, 2001 to March. 10, 2006. The empirical results are summarized as follows : First, irrespective of hedging period and model, hedging using Korea won/dollar futures reduces spot rate's volatility risk by 97%. Second, Korea won/dollar futures market produces the best hedging performance in emerging and advanced currency futures markets, i.e. Mexico peso, Brazil real, Europe euro, British pound, and Japan yen. Third, there are no difference of hedging effectiveness among hedging models.

• Korean Journal of Community Nutrition
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• v.19 no.5
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• pp.479-489
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• 2014

Objectives: This study intended to determine significant factors that influence the health-related quality of life ("HRQoL"; EuroQol 5 Dimension health-related quality of life (EQ_5D) & EuroQol visual analogue scale (EQ_VAS)) of the elderly in Korea. Methods: This study was based on 3,903 subjects aged 65 years or more who participated in the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V), 2010~2012. The HRQoL was analyzed by various factors (general characteristics, health habits, mental health, chronic diseases, nutrient intakes). SPSS statistics for complex samples (Windows ver. 21.0) was used. Results: The HRQoL was higher in the males, those with higher educational level or higher income level while it was lower in those belong to single households. In particular, the EQ_5D was significantly higher in the group who reported walking practice, moderate physical activity (male), and the group who reported no vigorous physical activity (female). The EQ_VAS was significantly higher in the group who reported walking practice. Both EQ_5D and EQ_VAS were significantly lower in the group with stress, melancholy, suicidal thinking, and osteoarthritis. EQ_5D was significantly lower in the group with < 75% Estimated Energy Requirements (EER) in energy intake, and with < Estimated Average Requirements (EAR) in iron or niacin intake. A stepwise regression analysis revealed that i) higher educational level (male), and good self-rated health status significantly increased the EQ_5D, ii) age, alcohol intake (male), melancholy (female), suicidal thinking, osteoarthritis, and niacin intake deficiency (male) significantly decreased the EQ_5D, iii) higher income level (male) and good self-rated health status significantly increased the EQ_VAS, and iv) age (male), stress, suicidal thinking (female) and osteoarthritis significantly decreased the EQ_VAS. Conclusions: This study suggested that general characteristics, mental health, osteoarthritis, and niacin intake were associated with the HRQoL. Prospective research of long-term control is needed to establish the causal relationship between factors and the HRQoL.

• Korean Journal of Acupuncture
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• v.37 no.1
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• pp.54-62
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• 2020

Objectives : Acute low back pain syndrome causes pain and poor quality of life. There are various studies of SBV (Sweet bee venom) pharmacopuncture, but few have identified the therapeutic effects for patients unable to walk due to acute back pain. This case series report three cases of acute low back pain syndrome treated with SBV pharmacopuncture combined with Korean Medicine (KM) treatments. Methods : Three acute low back pain syndrome patients with no other acute abnormalities in the imaging were treated by KM treatments including SBV pharmacopuncture, acupuncture, cupping, herbal medicine and physical therapy. The improvement of symptoms was evaluated using Numerical rating scale (NRS), Oswestry disability Index (ODI), EuroQol-5 dimension index (EQ-5D) and EuroQol-visual analogue scale (EQ-VAS). Results : Patients who were unable to walk due to acute back pain were able to walk. There were significant improvements of NRS, ODI, EQ-5D and EQ-VAS after treatment. The patients experienced an average 90% decrease in low back pain after inpatient KM treatment for about 8 days. NRS decreased by an average of 78.9%, ODI decreased by an average of 49.4%, and EQ-VAS increased by an average of 92.6%. In the case 1, EQ-5D decreased in all categories, but in the case 2, it decreased in all categories except for pain/discomfort and anxiety/depression, but in the case 3, it decreased in all categories except anxiety/depression. There was no serious side effect after treatment of SBV pharmacopuncture. Conclusions : KM treatments including SBV pharmacopuncture may be effective for acute low back pain syndrome patients. However, randomized controlled trials are needed in the future to confirm the clinical effects of these interventions.