• The Korean Journal of Pharmacology
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• v.31 no.1 s.57
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• pp.17-26
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• 1995

The present studies were carried out to determine if antinociceptive action of morphine and ${\beta}-endorphin$ administered intraventricularly was changed in. pentobarbital anesthetized spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Antinociception was assessed by the tail-flick test. The $ED_{50}$ values of antinociception for morphine administered intraventricularly were 1.9 and 1.2 nmol for WKY and SHR rats, respectively. The $ED_{50}$ values of antinociception for ${\beta}-endorphin$ administered intraventricularly were 0.40 and 0.12 nmol for WKY and SHR rats, respectively. The $[Met^5]-enkephalin$ (ME) and proenkephalin mRNA levels in midbrain, pons and medulla, or lumbar section of the spinal cord in WKY and SHR rats were measured by the radioimmunoassay and Northern blot assay, respectively. There were no differences of ME and proenkephalin mRNA levels in these tissues between WKY and SHR rats. The results suggest that ${\beta}-endorphin$ but not morphine administered intraventricularly produces a greater antinociception in SHR rats. This increased antinociceptive effect of ${\beta}-endorphin$ in SHR rats may be not, at least, due to the alterations of ME And proenkephalin mRNA levels in the midbrain, pons and medulla, or spinal cord.

• Journal of Advanced Marine Engineering and Technology
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• v.8 no.1
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• pp.17-36
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• 1984

Since 1973, the competition on the development of fuel saving type internal combustion engines has become severe by the two times oil shock, and new type engines are reported every several months. Whenever these new type engines are developed, new designs are required and they will be offered in the market after performing the endurance test for a long time. But the engine market is faced with a heavy burden of finance, as the developing of a new engine requires tremendous expenses. For this reason, the computer simulation method has been lately developed to cope with it. The computer simulation method can be available to perform the reasonable research works by the theoretical analysis before carrying out practical experiments. With these processes, the developing expenses are cut down and the period of development is curtailed. The object of this study is the development of simulation computer program for the small naturally aspirated four-stroke diesel engine which is intended to product by the original design of our country. The process of simulation is firstly investigated for the ideal engine cycle, and secondly for the real engine cycle. In the ideal engine cycle, each step of the cycle is simulated by the energy balance according to the first law of thermodynamics, and then the engine performance is calculated. In the real cycle imulation program, the injection rate, the preparation rate and the combustion rate of fuel and the heat transfer through the wall of combustion chamber are considered. In this case, the injection rate is supposed as constant through the crank angle interval of injection and the combustion rate is calculated by the Whitehouse-Way equation and the heat transfer is calculated by the Annand's equation. The simulated values are compared with measured values of the YANMAR NS90(C) engine and Mitsubishi 4D30 engine, and the following conclusions are drawn. 1. The heat loss by the exhaust gas is well agree with each other in the lower load, but the measured value is greater than the calculated value in the higher load. The maximum error rate is about 15% in the full load. 2. The calculated quantity of heat transfer to the cooling water is greater than the measured value. The maximum error rate is about 11.8%. 3. The mean effective pressure, the fuel consumption, the power and the torque are well agree with each other. The maximum error is occurred in the fuel consumption, and its error rate is about 7%. From the above remarks, it may be concluded that the prediction of the engine performance is possibly by using the developed program, although the program needs to reform by adding the simulation of intake and exhaust process and assumping more reliable mechanical efficiency, volumetric efficiency, preparation rate and combustion rate.

• The Journal of Korean Academy of Prosthodontics
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• v.17 no.1
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• pp.23-34
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• 1979

In this study, the adhesive strength of three commercial polycarboxylate cements to ten types of dental casting alloys, such as gold, palladium, silver, indium, copper, nickel, chromium, and human enamel and dentine were measured and compared with that of a conventional zinc phosphate cement. The $8.0mm{\times}3.0mm$ cylindrical alloy specimens were made by casting. The enamel specimens were prepared from the labial surface of human upper incisor, and the dentine specimens were prepared from the occulusal surface of the human molar respectively. Sound extracted human teeth, which had been kept in a fresh condition since, extraction, were mounted in a wax box with a cold-curing acrylic resin to expose the flattened area. The mounted teeth were then placed in a Specimen Cutter (Technicut) and were cut down under a water spray, and then the flat area on the all specimens were ground by hand with 400 and 600 grit wet silicone carbide paper. Two such specimens were then cemented together face-to-face with freshly mixed cement, and moderate finger pressure was applied to squeeze the cement to a thin and uniform film. All cemented specimens were then kept in a thermostatic humidor cabinet regulated at $23{\pm}2^{\circ}C.$ and more than 95 per cent relative humidity and tested after 24 hours and 1 week. Link chain was attached to each alloy specimen to reduce the rigidity of the jig assembly, and then all the specimens were mounted in the grips of the Instron Universal Testing Machine, and a tensile load was delivered to the adhering surface at a cross head speed of 0.20 mm/min. The loads to which the specimens were subjected were recorded on a chart moving at 0.50 mm/min. The adhesive strength was determined by measuring the load when the specimen separated from the cement block and by dividing the load by the area. The test was performed in a room at $23{\pm}2^{\circ}C.$ and $50{\pm}10$ per cent relative humidity. A minimum of five specimens were tested each material and those which deviated more than 15 per cent from the mean were discarded and new specimens prepared. From the experiments, the following results were obtained. 1) It was found that the adhesive strength of the polycarboxylate cement to all alloys tested was considerably greater than that of the zinc phosphate cement. 2) The adhesive strength of the polycarboxylate cements was superior to the non precious alloys, such as the copper, indium, nickel and chromium alloys, but it was inferior to the precious gold, silver and palladium alloys. 3) Surface treatment of the alloy was found to be an important factor in achieving adhesion. It appears that a polycarboxylate cement will adhere better to a smooth surface than to a rough one. This contrasts with zinc phosphate cements, where a rough helps mechanical interlocking. 4) The adhesion of the polycarboxylate cement with enamel was found superior to its adhesion with dentine.

• Journal of the Korean Geotechnical Society
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• v.15 no.6
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• pp.307-317
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• 1999

The purpose of this study is to utilize conventional procedures for evaluation of liquefaction potential and to compare the results obtained by modified detailed method based on Korean earthquake magnitude (M=6.5). Liquefaction potential is assessed by comparing liquefaction strength of soil and cyclic shear stress generated in the soil layers during earthquakes. The cyclic shear stress is computed from the earthquake response analysis, and liquefaction strength of soil is evaluated by using results from cyclic triaxial tests. The cyclic triaxial tests are performed on many different conditions of sample ; relative densities(50%, 60%, and 70%), initial effective confining pressures (70kPa, 100kPa, and 150kPa), and fine contents(10%, 20%, and 30%). From the result of comparing the conventional procedure with the modified detailed method, it is found that the modified detailed method tends to evaluate larger safety factor against liquefaction in the weak sand site$(FS \leq1.5)$. Therefore in this case, it is suggested that liquefaction potential should be evaluated by using the modified detailed method based on cyclic triaxial tests. It is also found that in modified detailed method based on earthquake magnitude 6.5, critical depth where liquefaction can be generated is around 15m from the ground surface.

• The Journal of Korean Academic Society of Nursing Education
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• v.9 no.1
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• pp.51-63
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• 2003

The purpose of this study was to identify the prevalence of urinary incontinence of community residing climacteric women, and to identify the relationship between urinary incontinence and quality of life. The subjects of this study were 156 women(45 to 59 years old). Data was collected from Sep. 1 to Dec. 1 2002 by an interview or self-reporting by a structured questionnaire. The questionnaire was composed of items of general characteristics, urinary characteristics, and conditions of urinary incontinence, using the modified Henderickson's stress incontinence scale(1981), and the quality of life scale developed by RO, You Ja(1988). The data was analyzed by the SPSS/WIN program using descriptive statistics, Pearson correlation coefficients, t-test and AVOVA. The results of the study were as follows : 1. The prevalence of urinary incontinence was 76.3%. Of the incontinent women, 42.0% had experienced urinary incontinence for a period of one to three years. Frequency of urinary incontinence was once or twice per day for 42.9% of the urinary incontinent women. Most of the participation with urinary incontinence(91.6%) had mild leakage of urine. In the whole urinary incontinent women, 70.6% had never treated or managed their urinary incontinence. Most of the subjects(79.8%) were mildly incontinent, and the prevalence of moderate and severe urinary incontinence was 20.2%. The mean scores among the items of urinary incontinence, in descending order, were increase of abdominal pressure($1.45{\pm}1.05$), coughing($1.16{\pm}0.93$), and sneezing($1.03{\pm}0.92$). 2. The average score in the level in the quality of life variables was 3.12. The urinary incontinence and quality of life were correlated negatively(r=-0.103, p<0.001). 3. There were statistically significant differences in the score of climacteric woman's self reported quality of life according to : amount of urinary incontinence(F=12.68, P=0.001), duration of urinary incontinence(F=6.97, P=0.009), number of urinary incontinence(F=4.77, P=0.03), existence of urinary incontinence(t=148, P=0.05). In conclusion, this study was a preliminary study to provide nursing practice guidelines for climacteric woman with urinary incontinence. Nurses working with climacteric woman should develop and provide adequate care for the incontinent climacteric subjects. In future research, it is recommended to identify comprehensive factors related to urinary incontinence, including the effective management of urinary incontinence.

• Journal of Dental Anesthesia and Pain Medicine
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• v.15 no.3
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• pp.129-134
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• 2015

Background: We hypothesized that ketamine, when administered as the anesthetic induction agent, may prevent cardiovascular depression during high-dose remifentanil administration, unlike propofol. To test our hypothesis, we retrospectively compared the hemodynamic effects of ketamine, during high-dose remifentanil administration, with those of propofol. Methods: Thirty-eight patients who underwent oral surgery at the Nagasaki University Hospital between April 2014 and June 2015 were included in this study. Anesthesia was induced by the following procedure: First, high-dose remifentanil ($0.3-0.5{\mu}g/kg/min$) was administered 2-3 min before anesthesia induction;next, the anesthetic induction agent, either propofol (Group P) or ketamine (Group K), was administered. Mean arterial pressure (MAP) and the heart rate were recorded by the automated anesthesia recording system at four time points: immediately before the administration of high-dose remifentanil (T1);immediately before the administration of propofol or ketamine (T2);2.5 min (T3), and 5 min (T4) after the administration of the anesthetic induction agent. Results: In Group P, the MAP at T3 ($75.7{\pm}15.5mmHg$, P = 0.0015) and T4 ($68.3{\pm}12.5mmHg$, P < 0.001) were significantly lower than those at T1 ($94.0{\pm}12.4mmHg$). However, the MAP values in the K group were very similar (P = 0.133) at all time points. The heart rates in both Groups P (P = 0.254) and K (P = 0.859) remained unchanged over time. Conclusions: We showed that ketamine, when administered as the anesthetic induction agent during high-dose remifentanil administration, prevents cardiovascular depression.

• Applied Chemistry for Engineering
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• v.5 no.5
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• pp.836-842
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• 1994

The optimum design conditions of gas sparger pipe and the effects of operating variables on $SO_2$ removal efficiency have been examined in Jet Bubbling Reactor. Geometry of gas sparser pipe of Jet Bubbling Reactor is a very important factor to obtain a effective gas-liquid contact. Test results revealed that Reynolds numbers at sparger and slot have to be kept greater than 12,000 identically at a given gas velocity. $SO_2$ removal efficiency was a function of ${\Delta}P$, pH, inlet $SO_2$ concentration and particle size of limestone and was more sensitive to the change of ${\Delta}P$ than to the changes of others. The ${\Delta}P$ of at least 230mmAq must be maintained to acheive the above 90% $SO_2$ removal at pH of 4.0 which is considered as adequate operating pH. Higher $SO_2$ removal efficiency was obtained even at lower pH ranges, which resulted from the complete oxidation of the absorbed $SO_2$ to sulfates by adding air and consequently from the reduction of $SO_2$ equillibrium partial pressure in the gas-liquid interface The 99.5% of the limestone utilization was attained in pH range from 3.0 to 5.0 with regardless to the particle size of limestone employed.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.420-426
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• 2017

Recently, solvent-resistant nanofiltration membranes have been studied for the separation of solvents or solutes using a molecular weight cut-off system of the polymer which is resistant to a specific solvent. Required conditions for these membranes must have are excellent physical properties and solvent resistance. Polybenzimidazole, which is known to be one of the most heat-resistant commercially available polymers, has an excellent inherent solvent resistance and it is even insoluble in stronger organic solvents when cross-linked. Therefore, in this study, the applicability of polybenzimidazole as a solvent resistant nanofiltration membrane was discussed. The membrane was fabricated using the non-solvent induced phase separation method and showed a suitable morphology as a nanofiltration membrane confirmed by field emission scanning electron microscopy. In addition, the permeance of the solvent in the presence or absence of cross-linking was investigated and the stability was also confirmed through long operation. The permeance test was carried out with five different solvents: water, ethanol, benzene, N, N-dimethylacetamide (DMAc) and n-methyl-2-pyrrolidone (NMP); each of the initial flux was $6500L/m^2h$ (water, 2 bar), $720L/m^2h$ (DMAc, 5 bar), $185L/m^2h$ (benzene, 5 bar), $132L/m^2h$ (NMP, 5 bar), $65L/m^2h$ (ethanol, 5 bar) and the pressure between 2 and 5 bar was applied depending on the type of membrane.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.30 no.2
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• pp.95-100
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• 2019

Background and Objectives For patients with polyps and cysts, glottal gaps resulting from their lesions have negative respiratory effects when they vocalize. Phonatory Aerodynamic System is clinically used, but is often limited in the measurement of vowels. So the researchers attempted to verify the usefulness of Phonatory Aerodynamic System by comparing differences in respiratory characteristics and patterns which can be measured by the level of connected speech. Materials and Method Among the subjects who were diagnosed through a stroboscopy, there were 33 patients with polyps and 23 patients with cysts. Then, 36 subjects who were found to have no specific findings through a stroboscopy and perceptual test were selected to the normal group. We compared respiratory characteristics and patterns. And compared vocal polyps and cysts before and after laryngeal micro surgery (LMS). Results First, difference in respiratory patterns between the normal group and the patients with polyps and cysts were examined to show that breath groups, breath group syllables, and expiratory·inspiratory volume were significantly higher in the polyp/cyst group than those in the normal group, indicating that precision was lowered during the conversation, due to reduction in speech intelligibility and interruption of communication. Second, there were significant differences in maximum phonation time, mean flow rate, and subglottal pressure among respiratory characteristics, breath groups, breath group syllables, and inspiratory volume before and after LMS, which appeared to be similar to the normal group. Conclusion The understanding of respiratory characteristics and patterns produced by patients in connected speech which is most similar to natural speech was found to be the objective and useful method for examining characteristics of the subjects.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.3
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• pp.233-239
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• 2013

A 100 W fuel cell system using chemical storage method has been applied for a propulsion system of the SUAV(Small Unmanned Aerial Vehicle). A fuel cell and battery have been combined for both the small/light hydrogen generation control system and the hybrid power supply system. A small hydrogen generation device was implemented to utilize NaBH4 aqueous solution and dead-end type PEMFC system, which were evaluated on the ground and by the flight tests. The system pressurized at a 45kpa stably operates and get higher fuel efficiency. The pressure inside of the hydrogen generation control system was maintained at between 45 kPa and 55 kPa. The 100W fuel cell system satisfies the required weight and power consumption rate as well as the propulsion system, and the fuel cell system performance was demonstrated through flight test.