• Journal of Korean Society of Transportation
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• v.24 no.2 s.88
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• pp.65-78
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• 2006

This paper investigates the cost structure ot the Korea and Japan railroad industry with respect to density, scale and scope economies as well as productivity growth rate using a generalized trans)og multiproduct cost function model. The paper then assumes that the Korea and Japan railway companies pi·educe three outputs (incumbent railway passenger-kilometers. Shinkansen passenger-kilometers, ton-kilometers of freight) using four input factors (labor, fuel, maintenance, rolling stock and capital). The specified cost function includes foul other independent variables: track lengths to reflect network effects, two dummies to reflect nation and ownership effects, and time trend as a proxy for technical change. The simultaneous equation system consisting of a cost function and three input share equations is estimated with the Zellner's iterative seemingly unrelated regression. The unbalanced panel data used in the paper, a total of 154 observations. are collected from the annual records of the Korea National Railroad (KNR) for the yews $1977{\sim}2003$, Japan National Railways (JNR) for the years $1977{\sim}1984$. seven Japan Railways (JR's) for the years $1987{\sim}2003$. The findings show that the Korean and Japanese railways exhibit product-specific and overall economies of density but product-specific diseconomies of scale with respect to incumbent railway passenger-kilometers, Shinkansen-kilometers and ton-kilometers. However, the railways experience mild overall economies of scale which result from economies of scope associated with the joint production of incumbent railway/Shinkansen and feight, freight/incumbent railway and Shinkansen except Shinkansen/incumbent railway and freight. In addition, the economies of density and scale in the KNR, JR east, JR central, and JR west companies at the point of the years $1990{\sim}2003$ average is generally analogous to the above results at the point of sample average. There also appear to be economies of ssope associated with the joint Production of the incumbent railway and Shinkansen in JR central but diseconomies of scope in JR East and JR West. The findings also indicate that the productivity growth rate of the privately-owned JR's is larger than that of the government-owned KNR.

• Journal of Chest Surgery
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• v.29 no.6
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• pp.606-613
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• 1996

Cardiac transplantation has been the treatment of patients with end-stage heart disease since it was first performed in 1967. In Korea the first case was performed in 1992 and 42 patients underwent heart trans- plantation so far. The purpose of this article is to report short-term result of cardiac transplantation at our center. Between April 1994 and September 1995, 14 patients had undergone orthotopic heart transplantations. There was 12 male and 2 female patients. Mea recipient age was 34 years(range 11 to 54 years) and mean donor age was 28.4 years(16 to 50 years). Mean graft ischemic time was 120.7minutes(80 to 280 minutes). The follow-up period after transplantation was 11 months(3 to 17 months). Recipient diagnosis included dilated cardiomyopathy in 10, ischemic cardiomyopathy in 2, valvular cardiomyopathy in 1, congenital complex heart disease in 1 patient. The preoperative status of the recipients were state I (50%) and ll (50%) by UNOS classification and class 111 (5 patients) and class IV (9) by NYHA functional class. All patients were treated with triple-drug immunosuppression (cyclosporine, azathioprine, steroid) and induction with RATG. The rejection episodes were 5 times in 3 patients during the follow-up. Causes of infection were aspergillosis (2), and hepes zoster (1), CMV pneumonitis (1). Permanent pace- maker was inserted in 1 patient. Currently 9 patients are alive with seven patients in WYHA functional class I and two in class l . The ejection fraction increased from preoperative value of 19.9 $\pm$ 3.4% to postoperative value of 69.0 $\pm$ 5.6%. The causes of death were cellular rejection (1),chronic graft failure due to size-mismatching (1),respirat- oxy insufficiency due to asthma attack (1), subarachnoid hemorrhage (1), and RIO humoral rejection (1).

• Korean Journal of Materials Research
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• v.6 no.7
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• pp.700-708
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• 1996

Electroless plating technique was utilized to flip chip bonding to improve surface mount characteristics. Each step of plating procedure was studied in terms pf pH, plating temperature and plating time. Al patterned 4 inch Si wafers were used as substrstes and zincate was used as an activation solution. Heat treatment was carried out for all the specimens in the temperature range from room temperature to $400^{\circ}C$ for $30^{\circ}C$ minutes in a vacuum furnace. Homogeneous distribution of Zn particles of size was obtained by the zincate treatment with pH 13 ~ 13.5, solution concentration of 15 ~ 25% at room temperature. The plating rates for both Ni-P and Au electroless plating steps increased with increasing the plating temperature and pH. The main crystallization planes of the plated Au were found to be (111) a pH 7 and (200) and (111) at pH 9 independent of the annealing temperature.

• Journal of Dairy Science and Biotechnology
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• v.33 no.2
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• pp.129-137
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• 2015

Diabetes mellitus type 2 is a metabolic disorder that is characterized by hyperglycemia (high blood sugar level) in the context of insulin resistance and relative lack of insulin. Recently, much scientific evidence has shown that the risk of diabetes mellitus type 2 could be reduced by dairy intake. A significantly strong relationship has been noted between this disease and dairy intake. In particular, from the different types of fat in dairy foods that were reported to have a beneficial impact, low-fat dairy foods have been found to have the best effect with respect to reducing the risk of diabetes mellitus type 2. Therefore, the role of specific components of dairy foods, such as calcium, vitamin D, dairy fat, and trans-palmitoleic acid, which could be responsible for this effect and for the positive effect of dairy foods in obesity and metabolic syndrome, needs to be identified. There is a strong and relatively consistent body of accumulating evidence indicating that dairy foods may significantly reduce the risk of diabetes mellitus type 2, likely in a dose-response manner. Dairy recommendations should be an essential part of public health guidance, and identifying strategies to increase dairy food consumption to optimal levels is of utmost importance. Hence, this review summarizes various positive effects of dairy foods with respect to reducing the risk of diabetes mellitus type 2, based on available evidence, and discusses the need for further research on preventing or decreasing the risk of diabetes mellitus type 2.

• Journal of Nutrition and Health
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• v.43 no.2
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• pp.181-188
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• 2010

Consumer perception of processed food and restaurant food's nutrient labelling was surveyed. The subjects of this survey consisted of 1,507 parents, whose ages were 20-59 years old. The ratio of the respondents that have known nutrition labelling on processed foods was 89.8% and the ratio of whom have checked the nutrition labelling at their point of purchase was 72.3%. The nutrients which were considered important for nutrition labelling were fat (57.1%), calorie (56.3%) and sodium (49.0%). Also nutrient which were able to be recognized at a glance by the subjects were in the order of trans fat (62.1%), cholesterol (26.9%), calorie (23.9%) and sodium (21.0%). If restaurant menu's nutrient labelling be enacted, the answer rate that the menu's nutrition labelling may affect their menu choice is 90.6% of the respondents. Besides of the Fastfoods that are enforcement, restaurants of that customers want the menu to be labeled were 'pizza and chicken restaurants'. Nutrients that customers preferred to be labelled were calorie (62.0%), fat (60.3%) and sodium (50.9%).

• Journal of Nutrition and Health
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• v.41 no.8
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• pp.839-850
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• 2008

This study describes the demographic and diet-related psychosocial correlates of nutrition label use, and examines the relationship between label use and diet. Self-reported dada from a population-based cross-sectional survey of 2073 Korean women aged 20 to 60 years were collected to identify demographic and health-related characteristics, belief on diet-disease relationship, awareness on importance of healthy eating practice and diet quality associated with label use. Label users, who are in the stage of action and maintenance (31.6%), were more likely to have belief on nutrient-disease relationship (in sodium, cholesterol, sugar and trans fat) and were more likely to have higher awareness of the importance of healthy eating practice compared with label nonusers, who are in the stage of precontemplation, contemplation and preparation. Label users were more likely to have higher dietary quality compared with label nonusers [odds ratio (OR) = 2.01; 95% confidence interval (CI): 1.66, 2.44](P < 0.001). Also, label use appeared to be associated with the consumption of diets that were higher vegetables and fruits, and lower in cholesterol. The findings of this study suggests that reading nutrition labels on food packages may improve food choices and enable healthful dietary practices.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.4
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• pp.307-316
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• 2010

Complex terrain refers to irregular surface properties of the earth that influence gradients in climate, lateral transfer of materials, landscape distribution in soils properties, habitat selection of organisms, and via human preferences, the patterning in development of land use. Complex terrain of mountainous areas represents ca. 20% of the Earth's terrestrial surface; and such regions provide fresh water to at least half of humankind. Most major river systems originate in such terrain, and their resources are often associated with socio-economic competition and political disputes. The goals of the TERRECO-IRTG focus on building a bridge between ecosystem understanding in complex terrain and spatial assessments of ecosystem performance with respect to derived ecosystem services. More specifically, a coordinated assessment framework will be developed from landscape to regional scale applications to quantify trade-offs and will be applied to determine how shifts in climate and land use in complex terrain influence naturally derived ecosystem services. Within the scope of TERRECO, the abiotic and biotic studies of water yield and quality, production and biodiversity, soil processing of materials and trace gas emissions in complex terrain are merged. There is a need to quantitatively understand 1) the ecosystem services derived in regions of complex terrain, 2) the process regulation occurred to maintain those services, and 3) the sensitivities defining thresholds critical in stability of these systems. The TERRECO-IRTG is dedicated to joint study of ecosystems in complex terrain from landscape to regional scales. Our objectives are to reveal the spatial patterns in driving variables of essential ecosystem processes involved in ecosystem services of complex terrain region and hence, to evaluate the resulting ecosystem services, and further to provide new tools for understanding and managing such areas.

• The Korean Journal of Pharmacology
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• v.10 no.1 s.15
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• pp.31-40
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• 1974

1. The authors investigated the effects of $PGE_1$ on the action of sympathomimetics in the vas deferens of guinea-pig, comparing with those in the rat vas deferens, and also the action of $PGE_1$ on the motility of nerve-free smooth muscle of chick amnion. 2. In the isolated guinea-pig vas deferens, the actions of phenylephrine and norepinephrine were much potentiated by pretreatment with $PGE_1$. Futher, in the isolated hypogastric nerve-vas deferens preparation of guinea-pig, effects of phenylephrine, norepinephrine and tyramine on the contractile response of vas to the hypogastric nerve stimulation and to the transmural stimulation were also augumented especially in tension by $PGE_1$-pretreatment. 3. In the isolated hypogastric nerve-vas preparation of rat, both contractile responses to hypogastric nerve and transmural stimulation were slowly reduced by treatment with $PGE_1$ and the potentiated effect of phenylephrine or norepinephrine was not observed in spite of pretreatment with $PGE_1$. 4. The actions of phenylephrine and norepinephrine on the denervated vas deferens of guinea-pig were also enhanced by $PGE_1$ as it were in the intact vas deferens, but there was no significant effect by $PGE_1$ on the action of norepinephrine in the denervated rat vas deferens. 5. $PGE_1$ in low concentration $(10^{-8}g/ml)$ did not affect the spontaneous motility of nerve-free smooth muscle of chick amnion ($9{\sim}11$ th day incubated chick), but in large concentration $(5{\times}10^{-8}g/ml)$ it caused irregular and slightly inhibitory movement. Pretreatment with $PGE_1$ on chick amnion did not exert any change on the action of phenylephrine applied. However, the stimulatory action of physostigmine on the chick amnion was a little antagonized by the low concentration of $PGE_1$. 6. It might be summarized that there is species difference between the actions of $PGE_1$ on the vas deferens of guinea-pig and that of rat, and the action of $PGE_1$ on the guinea-pig vas deferens might be mediated by the other mechanism rather than by direct action on the vas musculature.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.330-338
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• 2002

This study was performed to develop natural spices and functional foods using Cheongung (Cnidium officinale) which is one of the Korean medicinal plants. The volatile flavor patterns of Cnidium officinale were detected by electronic nose with 6 metal oxide sensors, and the principal component analysis was carried out. The volatile flavor components of Cnidium officinale were isolated by simultaneous steam-distillation extraction with pentane and diethylether (1 : 1), and essential oils were analyzed by capillary GC and GC/MS. The free radical scavenging activity of ethanol and methanol extracts from Cnidium officinale was measured by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and compared with ${\alpha}-tocopherol$ as reference. The principal component analysis showed the difference of principal components between fresh and drying samples. Eighty-five volatile flavor components (643.64 ppm) from fresh Cnidium officinale were identified and the major components were butyl phthalide, sabinene, neocnidilide. Sixty-four volatile flavor components (218.15 ppm) from hot air dried one were identified and the major components were butyl phthalide, sabinene, 3-N-butyl phthalide. And 73 volatile flavor components (784.15 ppm) from freeze dried one were identified and the major components were butyl phthalide, sabinene, ${\beta}-selinene$. The free radical scavenging activity of methanol cold extract (500 ppm) of freeze dried Cnidium officinale was higher than other samples. And methanol and ethanol cold extracts (above 250 ppm) of freeze dried sample were higher than ${\alpha}-tocopherol$ $25\;{\mu}M$ (22.34%).

• Tuberculosis and Respiratory Diseases
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• v.46 no.6
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• pp.846-855
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• 1999

Background : Secondary pulmonary hypertension is an important final endpoint in patients with chronic hypoxic lung disease, accompanied by deterioration of pulmonary hemodynamics. The clinical diagnosis of pulmonary hypertension and/or cor pulmonale could be difficult, and simple noninvasive evaluation of pulmonary artery pressures has been an relevant clinical challenge for many years. Doppler echocardiography might to be a more reliable method for evaluating pulmonary hemodynamics in such patients in terms of the accuracy, reproducibility and easiness for obtaining an appropriate echocardiographic window than M-mode echocardiography. The aim of this study was to assess echocardiographic parameters associated with pulmonary arterial hypertension, defined by increasing right ventricular systolic pressure(RVSP), calculated from trans-tricuspid gradient in patients with chronic hypoxic lungs. Method : We examined 19 patients with chronic hypoxic lung disease, suspected pulmonary hypertension under the clinical guidelines by two dimensional echocardiography via the left parasternal and subcostal approach in a supine position. Doppler echocardiography measured RVSP from tricuspid regurgitant velocity in continuous wave with 2.5MHz transducer and acceleration time(AT) on right ventricular outflow tract in pulsed wave for the estimation of pulmonary arterial pressure. Results : On echocardiography, moderate to severe degree of pulmonary arterial hypertension was defined as RVSP more than 40mmHg, presenting tricuspid regurgitation. Increased right ventricular endsystolic diameter and shortened AT were noted in the increased RVSP group. Increased RVSP was correlated negatively with the shortening of AT. Other clinical data, including pulmonary functional parameters, arterial blood gas analysis and M mode echocardiographic parameters were not changed significantly with the increased RVSP. Conclusion : These findings suggest that shortened AT on pulsed doppler can be useful when quantifying pulmonary arterial pressure with increased RVSP in patients with chronic lung disease with hypoxemia. Doppler echocardiography in pulmonary hypertension of chronic hypoxic lungs is an useful option, based on noninvasiveness under routine clinical practice.