• The Korean Journal of Physiology
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• v.9 no.1
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• pp.45-56
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• 1975

Various factors influencing the lymph flow from thoracic duct were investigated in an attempt to evaluate their contributing degree and the mechanisms. Sixteen mongrel dogs weighing between 10 and 16 kg were anesthetized and polyethylene catheters were inserted into the thoracic duct and femoral veins. Arterial blood pressure, heart rate, central venous pressure, lymph pressure and lymph flow were measured under various conditions. Electrical stimulation of left sciatic nerve, stepwise increase of central venous pressure, manual application of rhythmical depressions onto abdomen, injection of hypertonic saline solution and histamine infusion were employed. Measurement of cental venous pressure was performed through the recording catheter inserted into abdominal inferior vena cava. Changes in central venous pressure were made by an air-ballooning catheter located higher than the tip of the recording catheter in the inferior vena cava. Lymph flow from thoracic duct was measured directly with a graduated centrifuge tube allowing the lymph to flow freely outward through the inserted cannula. The average side pressure of thoracic lymph was $1.1\;cmH_2O$ and lymph flow was 0.40 ml/min or 1.9 ml/kg-hr. Hemodynamic parameters including lymph flow were measure immediately before and after (or during) applying a condition. Stimulation of left sciatic nerve with a square wave (5/sec, 2 msec, 10V) caused the lymph flow to increase 1.4 times. The pattern of lymph flow from thoracic duct was not continuous throughout the respiratory cycle, but was continuous only during Inspiration. Slow and deep respiration appeared to increase the lymph flow than a rapid and shallow respiration. Relationship between central venous pressure and the lymph flow revealed a relatively direct proportionality; Regression equation was Lymph Flow (ml/kg-hr)=0.09 CVP$(cmH_2O)$+0.55, r=0.67. Manual depressions onto the abdomen in accordance with the respiratory cycle caused the lymph flow to increase most remarkably, e.g,. 5.5 times. The application of manual depressions showed a fluctuation of central venous pressure superimposed on the respiratory fluctuation. Hypertonic saline solution (2% NaCl) administered Intravenously by the amount of 10 m1/kg increased the lymph flow 4.6 times. The injection also increased arterial blood pressure, especially systolic Pressure, and the central venous pressure. Slow intravenous infusion of histamine with a rate of 14-32 ${\mu}g/min$ resulted in a remarkable increase in the lymph flow (4.7 times), in spite of much decrease in the blood pressure and a slight decrease in the central venous pressure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.320-326
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• 2017

Multistage deep-drawing technology is used widely in the production of mobile phone battery cases to improve productivity and economy. To ensure adequate capacity and rigidity, such cases are fabricated as a rectangular cup with a high slender ratio. The multistage deep-drawing of a rectangular cup entails a high slender ratio, and the heights of the product sides may be non-uniform because of the complicated deformation mechanisms. This causes problems in product assembly that affects the surface quality of the case. This study examined a blank shape that minimizes the height variations of the product to resolve the aforementioned problems. Optimization design and analysis were performed to identify the shape that yields the least variation. The long and short sides of an oval blank were set as the design variables. The objective function was set to yield the lowest height difference, and the thickness reduction rate of the product was set to the target range. In addition, the height of the final shape was set as a constraint. The height difference was minimized successfully using the optimized design. The design process of the initial blank for all rectangular shapes can be automated in the future.

• Journal of the Korean Vacuum Society
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• v.21 no.1
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• pp.29-35
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• 2012

The Hydrogenated silicon nitride (SiNx:H) using plasma enhanced chemical vapor deposition is widely used in photovoltaic industry as an antireflection coating and passivation layer. In the high temperature firing process, the $SiN_x:H$ film should not change the properties for its use as high quality surface layer in crystalline silicon solar cells. Initially PECVD-$SiN_x:H$ film trends were investigated by varying the deposition parameters (temperature, electrode gap, RF power, gas flow rate etc.) to optimize the process parameter conditions. Then by varying gas ratios ($NH_3/SiH_4$), the hydrogenated silicon nitride films were analyzed for its optical, electrical, chemical and surface passivation properties. The $SiN_x:H$ films of refractive indices 1.90~2.20 were obtained. The film deposited with the gas ratio of 3.6 (Refractive index=1.98) showed the best properties in after firing process condition. The single crystalline silicon solar cells fabricated according to optimized gas ratio (R=3.6) condition on large area substrate of size $156{\times}156mm$ (Pseudo square) was found to have the conversion efficiency as high as 17.2%. Optimized hydrogenated silicon nitride surface layer and high efficiency crystalline silicon solar cells fabrication sequence has also been explained in this study.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8281-8285
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• 2016

Background: Helicobacter pylori is a cause of chronic gastritis, peptic ulcer disease, and gastric malignancy, infection being a serious health problem in Thailand. Recently, clarithromycin resistant H. pylori strains represent the main cause of treatment failure. Therefore this study aimed to determine the prevalence and pattern of H. pylori resistance to clarithromycin in Suranaree University of Technology Hospital, Suranree University of Technology, Nakhon Ratchasima, Northeastern Thailand, Nakhon Ratchasima province, northeast of Thailand. Materials and Methods: This hospital-based cross-sectional study was carried out between June 2014 and February 2015 with 300 infected patients interviewed and from whom gastric mucosa specimens were collected and proven positive by histology. The gastric mucosa specimens were tested for H. pylori and clarithromycin resistance by 23S ribosomal RNA point mutations analysis using real-time polymerase chain reactions. Correlation of eradication rates with patterns of mutation were analyzed by chi-square test. Results: Of 300 infected patients, the majority were aged between 47-61 years (31.6%), female (52.3%), with monthly income between 10,000-15,000 Baht (57%), and had a history of alcohol drinking (59.3%). Patient symptoms were abdominal pain (48.6%), followed by iron deficiency anemia (35.3%). Papaya salad consumption (40.3%) was a possible risk factor for H. pylori infection. The prevalence of H. pylori strains resistant to clarithromycin was 76.2%. Among clarithromycin-resistant strains tested, all were due to the A2144G point mutation in the 23S rRNA gene. Among mutations group, wild type genotype, mutant strain mixed wild type and mutant genotype were 23.8%, 35.7% and 40.5% respectively. With the clarithromycin-based triple therapy regimen, the efficacy decreased by 70% for H. pylori eradication (P<0.01). Conclusions: Recent results indicate a high rate of H. pylori resistance to clarithromycin. Mixed of wild type and mutant genotype is the most common mutant genotype in Nakhon Ratchasima province, therefore the use of clarithromycin-based triple therapy an not advisable as an empiric first-line regimen for H. pylori eradication in northeast region of Thailand.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.695-699
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• 2012

The objective of this study was to set the optimal extraction condition of flavonoids from onion peels as a by-product generated from the onion industry without suitable processing. Four independent variables, affecting extraction conditions, which are solvent concentration ($X_1$), extraction temperature ($X_2$), pH of the solvent ($X_3$), and solvent ratio to onion peel ($X_4$) were optimized using response surface methodology (RSM). A model equation obtained from RSM is 0.772 of R-square and 0.278 of lack of fit (p>0.05) for the optimal extraction conditions. From the ridge analysis, the conditions flavoring the highest extraction were solvent concentration (v/v) of 70%, extraction temperature of $40^{\circ}C$, extraction solvent pH of 5.3, and a solvent ratio to onion peel ratio of 1:63 (w/v). The flavonoid content obtained under optimal conditions showed 302.63 mg/g, which is 1.12 times higher than the prediction value.

• Strategy21
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• s.43
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• pp.29-55
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• 2018

Arctic sea ice has been retreating as a result of the global warming. Arctic sea ice extent for April 2018 averaged 13.71 million square kilometers. This figure shows far less sea ice compared to the average extent from 1981 to 2010. Meanwhile, 287 times of maritime transits through the Northwest Passage have been made during the 2017 and the first ship traversed the Northern Sea Route without the assistant of ice-breaker in August 2017. Commercialization of the Arctic Passage means significant economic and strategic advantages by shortening the distance. In this article, 'Arctic Passage' means Northern Sea Route along the Arctic coast of Russia and Northwest Passage crossing Canadian Arctic Ocean. As climate changes, the potential feasibility of the Arctic Passage has been drawing international attention. Since navigation in this area remains hazardous in some aspects, IMO adopted Polar Code to promote safe, secure and sustainable shipping through the Arctic Passage. Futhermore, Russia and Canada regulate foreign vessels over the maritime zones with the authority to unilaterally exercise jurisdiction pursuant to the Article 234 of UNCLOS. The dispute over the navigation regime of the arctic passage materialized with Russia proclaimed Dmitrii Laptev and Sannikov Straits as historically belong to U.S.S.R. in the mid 1960s and Canada declared that the waters of the passage are historic internal waters in 1973 for the first time. So as to support their claims, In 1985, Russia and Canada established straight baseline including Northern Sea Route and Northwest Passage. The United States has consistently protested that the Northern Sea Route and Northwest Passage are straits used for international navigation which are subject to the regime of transit passage. Firstly, it seems that Russia and Canada do not meet the basic requirements for acquiring a historic title. Secondly, since the Law of the Sea had adopted before the establishment of straight baseline over the Russian Arctic Archipelago and the Canadian Arctic Archipelago, Ships can exercise at least the right of innocent passage. Lastly, Northern Sea Route and Northwest Passage have fulfilled the both geographical and functional criteria pertaining to the strait used for international navigation under the international law. Especially, should the arctic passage become commercially viable, it can be expected to accumulate the functional criterion. Russia and Canada regulate the ships navigate in their maritime zones by adopting the higher degree of an environmental standard than generally accepted international rules and standard mainly under the Article 234 of UNCLOS. However, the Article 234 must be interpreted restrictively as this contains constraint on the freedom of navigation. Thus, it is reasonable to consider that the Article 234 is limited only to the EEZ of coastal states. Therefore, ships navigating in the Arctic Passage with the legal status of the territorial sea and the international straits under the law of the sea have the right of innocent passage and transit passage as usual.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.151-160
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• 2003

The stability of the designed rock slope is analysed based on two kinds of shear strength model. Besides the deterministic analysis, a probabilistic approach on Monte Carlo simulation is proposed to deal with the uncertain characteristics of the discontinuity and the results obtained from two models are compared to each other. To carry out the research of characteristics of the discontinuity, BIPS, DOM Scanline survey data and direct shear test data are used, and chi-square test is used for determining the probability distribution function. The rock slope is evaluated to be stable in the deterministic analysis, but in the probabilistic analysis, the probability of failure is more than 5%, so, it is considered that the rock slope is unstable. In the shear strength models, the probability of the failure based on the Mohr-Coulomb model(linear model) is higher than that of the Barton model. It is supported by the fact that the Mohr-Coulomb model is more sensitive to block size than the Barton model. In fact, there is no reliable way to estimate the unit cohesion of the Mohr-Coulomb model except f3r back analysis and in the case of small block failure in the slope, Mohr-Coulomb model may excessively evaluate the factor of the safety. So, the Barton model of which parameters are easily acquired using the geological survey is more reasonable for the stability of the studied slope. Also, the selection of the proper shear strength model is an important factor for slope failure analysis.

• Journal of Families and Better Life
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• v.27 no.1
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• pp.73-88
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• 2009

The purpose of this study was to investigate the influence of the factors such as self-esteem, social supports, socio-economic status of parents, degree of disability in child, stress coping, religion, and sports.exercise on the qualities of lives in mothers with disabled children. Data were collect from 45 institutions(schools from kindergarten to senior-high, special education institutes, and social welfare institutions) by self-report questionnaire, and the subjects of the study were 386 mothers in Seoul whose children were attending the schools or institutions. Findings according to socio-demographic variables are as follows: 1. Mothers with disabled children in this study thought their quality of life as average degree. 2. The younger the mothers and children, the higher the quality of life was. 3. The higher the educational level and monthly income, the higher the quality of life was. 4. There was no statistically significant difference between the existence and nonexistence of spouse, and between the existence and nonexistence of religion as well. Findings analyzed by multiple regression are as follows: 1. Among 7 independent variables 'self-esteem'(${\beta}$=.49, p<.001), 'social supports'(${\beta}$=.15, p<.01), and 'socio-economic status'(${\beta}$=.11, p<.05) were found to be statistically significant in quality of life in mothers, while the rests were found not significant. 2. 'Self-esteem' was found to be the most influencing variable, meaning that the psychological factor such as self-esteem is more important than environmental factors in qualities of lives in mothers. 3. The total amount of explanation of the model was Adjusted R square=.301, so that it can be said about 30% can be explained among total variance of the qualities of lives in mothers with disabled children. Conclusions and recommendations based on the results above are: First, it is strongly recommended to conduct programs promoting self-esteem in mothers with disabled children, and to include 'self-esteem' hereafter in the studies related to qualities of lives in mothers with disabled children. Second, comprehensive and practical countermeasures should to be formulated to back up expenses for education and medical care, purchasing relative tools and equipments, plus helping to find jobs.

• Journal of Periodontal and Implant Science
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• v.33 no.2
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• pp.159-166
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• 2003

The purpose of this study was to investigate and compare the frequence of 4 periodontal pathogens in the supra- and subgingival plaque in periodontally healthy subjects. Twenty adult individuals aged 22 to 28 years (mean age 23.65 years) participated in this study. All subjects had no pocket sites more than 3 mm deep, and the sites selected for sampling were all negative for bleeding. After drying and isolation of the sites with cotton rolls, supragingival plaque was sampled using sterile periodontal curette. Each plaque sample was placed in individual tubes containing 500 ml of 1X PBS. After removal of the supragingival sample and any remaining supragingival plaque, subgingival plaque samples were taken from the same sites using sterile curette and placed in similar individual tubes. Identification of 4 putative periodontal pathogens from the samples was performed by polymerase chain reaction based on 16S rDNA. Chi-square test was employed to identify significant explanatory variables for the presence of the 4 periodontal pathogens. The data show that Actinobacillus actinmycetemcomitans, Porphyromonanas gingivalis, Bacteroides forsythus, and Fusobacterium nucleatum occurred in 16.9%, 14.4%, 52.5%, and 80.6%, respectively. No significant differences were noted in the periodontal pathogens between supra- and subgingival plaques according to the kind of teeth. However, the incisors were at higher risk for harboring F. nucleatum (p <0.05). Conclusion: These results reveal that anaerobic periodontal pathogens can be detected in supragingival plaques. Supragingival plaque may function as a reservoir of peri-odotopathogens.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.5
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• pp.361-366
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• 2017

As the recent development of computing architecture and application software technology, real world simulation, which is the ultimate destination of computer simulation, is emerging as a practical issue in several research sectors. In this paper, metal plate motion in a square shock tube for small time interval was calculated using a supercomputing-based fluid-structure-combustion multi-physics simulation tool called Illinois Rocstar, developed in a US national R amp; D program at the University of Illinois. Afterwards, the simulation results were compared with those from experiments. The coupled solvers for unsteady compressible fluid dynamics and for structural analysis were based on the finite volume structured grid system and the large deformation linear elastic model, respectively. In addition, a strong correlation between calculation and experiment was shown, probably because of the predictor-corrector time-integration scheme framework. In the future, additional validation studies and code improvements for higher accuracy will be conducted to obtain a reliable open-source software research tool.