• Journal of the Korean Institute of Gas
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• v.24 no.2
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• pp.1-8
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• 2020

Centrifugal pump is a facility that transfers energy to fluid through centrifugal force, which is usually generated by rotating the impeller at high speed, and is a major process facility used in many LNG production bases such as vaporization seawater pump, industrial water and fire extinguishing pump using seawater. to be. Currently, pumps in LNG plant sites are subject to operating conditions that vary depending on the amount of supply desired by the customer for a long period of time. Pumps in particular occupy a large part of the consumption strategy at the plant site, and if the optimum operation condition is not available, it can incur enormous energy loss in long term plant operation. In order to solve this problem, it is necessary to identify the performance deterioration factor through the flow analysis and the result analysis according to the fluctuations of the pump's operating conditions and to determine the optimal operation efficiency. In order to evaluate operation efficiency through experimental techniques, considerable time and cost are incurred, such as on-site operating conditions and manufacturing of experimental equipment. If the performance of the pump is not suitable for the site, and the performance of the pump needs to be reduced, a method of changing the rotation speed or using a special liquid containing high viscosity or solids is used. Especially, in order to prevent disruptions in the operation of LNG production bases, a technology is required to satisfy the required performance conditions by processing the existing impeller of the pump within a short time. Therefore, in this study, the rotation difference of the pump was applied to the ANSYS CFX program by applying the modified 3D modeling shape. In addition, the results obtained from the flow analysis and the curve fitting toolbox of the MATLAB program were analyzed numerically to verify the outer diameter correction theory.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.141-152
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• 2020

The rapid on-site measurement of hydroponic nutrients allows for the more efficient use of crop fertilizers. This paper reports on the development of an embedded on-site system consisting of multiple ion-selective electrodes (ISEs) for the real-time measurement of the concentrations of macronutrients in hydroponic solutions. The system included a combination of PVC ISEs for the detection of NO₃, K, and Ca ions, a cobalt-electrode for the detection of H₂PO₄, a double-junction reference electrode, a solution container, and a sampling system consisting of pumps and valves. An Arduino Due board was used to collect data and to control the volume of the sample. Prior to the measurement of each sample, a two-point normalization method was employed to adjust the sensitivity followed by an offset to minimize potential drift that might occur during continuous measurement. The predictive capabilities of the NO₃ and K ISEs based on PVC membranes were satisfactory, producing results that were in close agreement with the results of standard analyzers (R² = 0.99). Though the Ca ISE fabricated with Ca ionophore II underestimated the Ca concentration by an average of 55%, the strong linear relationship (R² > 0.84) makes it possible for the embedded system to be used in hydroponic NO₃, K, and Ca sensing. The cobalt-rod-based phosphate electrodes exhibited a relatively high error of 24.7±9.26% in the phosphate concentration range of 45 to 155 mg/L compared to standard methods due to inconsistent signal readings between replicates, illustrating the need for further research on the signal conditioning of cobalt electrodes to improve their predictive ability in hydroponic P sensing.

• Korean Journal of Biological Psychiatry
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• v.14 no.3
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• pp.167-176
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• 2007

Objectives:A considerable number of pharmacogenetic studies have been performed in recent years to define the association of antipsychotic drug response with dopamine receptor polymorphisms. The purpose of this study was to investigate the relationship between the therapeutic response to antipsychotic drugs and the polymorphisms of the dopamine D2, D3, and D4 receptor genes(DRD2, DRD3 and DRD4, respectively). Methods:We conducted retrospective chart review of 200 consecutively hospitalized patients with the diagnosis of schizophrenia(DSM-IV) who were treated with various antipsychotics(94% atypical antipsychotics) at Bugok National Hospital, Korea. The patients were divided into two groups, responders and non-responders, by responsiveness to antipsychotic drugs according to a four-point scale used in previous studies; responders included moderate to marked responded patients and non-responders included none to minimal responded patients. We analyzed the Ser311Cys polymorphism in the DRD2, the Ser9Gly polymorphism in the DRD3, and the exon III 48 bp repeat polymorphism in the DRD4. Results:Among the total patients of 200, 141(70.5%) were categorized as responders. There were no significant differences in the frequencies of the DRD2, DRD3, and DRD4 alleles and genotypes between responders and non-responders. Conclusion:These results suggest that the Ser311Cys polymorphism in the DRD2, the Ser9Gly polym- orphism in the DRD3, and the exon III 48bp repeat polymorphism in the DRD4 are not associated with the therapeutic response to antipsychotic drugs in Korean schizophrenic patients. A larger prospective study is needed to elucidate the association between antipsychotic response and dopamine receptor gene polymorphism.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.135-147
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• 1985

The authors studied neuroticism, using Eysenck's Maudsley Personality Inventory (MPI), in 3,893 male college students and 1,976 female college students of Yeungnam University. There was significant difference in the mean averages of total neuroticism scores between male and female students, male students scored $13.45{\pm}7.44$, female students scored $16.89{\pm}7.19$. The items relating to (16) Do you sometimes feel happy, sometimes depressed, without any apparent reason? (38) Do you daydream a lot? (1) Do you have dizzy turns? (2) Do you get palpitations or thumping in your heart? and (35) Do you worry about your health? were scored highly in male, and the items relating to (16) Do you sometimes feel happy, sometimes depressed, without any apparent reason? (1) Do you have dizzy turns? (38) Do you daydream a lot? (8) Do you worry too long over humiliating experiences? (9) Do you consider yourself rather a nervous person? were scored highly in female. Three hundreds and ninety eight male students (10.3%) showed seriously high neuroticism scores of 24 or higher, while 256 female students (13.0%) showed high neuroticism scores of 26 or higher. In a comparison between male students in different school grades, freshman showed the highest level of neuroticism scores. Among the psychosocial factors, there were strong tendencies toward higher neuroticism scores in the students who were dissatisfied with their colleges or departments, and who had pessimistic views of self-image in the past, present, or future in both groups. The male students whose educational fees were paid by their parents, and whose spending money per month was under 10,000 won, showed higher neuroticism scores. The female students whose educational fees were paid by their brothers or sisters, and whose maturation locations were U-P, and who resided in dormitory or other residencies, showed higher neuroticism scores.

• Journal of Mushroom
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• v.7 no.3
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• pp.130-134
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• 2009

To develop new white variety of Oyster mushroom, all white varieties which have been collected and kept in the lab were revived and screened their cultural characteristics. 84 intra-specific Oyster mushroom hybrids between the white-colored mutants Suhan and Wonhyeong were developed using hyphal anastomosis technique in 2007. The Po2007-63 ($2842-7{\times}0205-7$) was shown the best cultural characteristics, selected to be a new variety and named as 'Goni'. The new commercial strain, 'Goni' has white pilei and grows well under spring and autumn conditions in Korea. The fruiting bodies of 'Goni' are of an excellent quality in that not only the stipe is thick and long but also the pileus is small and hard. The optimum temperatures for mycelial growth and fruiting body development were $25-30^{\circ}C$ and $10-16^{\circ}C$, respectively. Time period required for the initiation of the first fruiting body is about 3 to 5 days depending on the temperatures. The shape of fruiting body is thin funnel shape. Fruiting body production per bottle was about $91{\pm}13$ g which is almost 97% quantity compared to that of other variety 'Miso'. Relatively low temperature incubation ($11^{\circ}C$) resulted in the development of better quality of 'Goni' mushrooms. When two different media including potato dextrose medium and mushroom complete medium were compared, the growth of mushroom were much faster in mushroom complete medium at $20-25^{\circ}C$, but not at $25^{\circ}C$. Similar results were observed with other variety 'Miso'. Analysis of the genetic characteristics of the new commercial strain 'Goni' showed a major DNA profile as that of the parental Suhan when primer URP 1 was used, but different to 'Miso' that was used as a control. When screens were performed with primer URP 2, DNA patterns were similar both to that of the parents and 'Miso'. This new variety of the white Oyster mushroom has a clean and fresh image that corresponds well to "health food". We therefore expect that this new strain will satisfy the consumers demand for variety and excellent mushrooms.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.2 s.51
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• pp.169-177
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• 2005

The propensity to purchase babies' cosmetics is investigated and analysed for this research. The synopsis of this research paper is as follows. The first, the $68\%$ of all respondents do not how a manufacturer or brand name in the reality of variously emerging domestic and import cosmetics for babies. The second, in case of a child haying a fair, sensitive skin or atopy (atopic dermatitis), the respondents are careful in choosing babies cosmetics but in case of a child having a normal skin the older a child grows from a stage of a new-born, a baby and an infant to a primary-school child, the older its mother is, the more respondents use adults' cosmetics in common rather than use cosmetics only for babies. $7.6\%$ of respondents do not use babies' cosmetirs at ail. Especially, in using bathing goods such as a shampoo or a body cleanser, they frequently use adults' cosmetics in common. The third, the qualify is taken into the utmost consideration in purchasing babies' cosmetics. The Quality of imports is trusted and preferred better than that of domestic goods. The cost of purchasing babies cosmetics is less than 10,000 Won. consumers recognize that the price or cosmetics is rather high. The last, the improvement or babies cosmetics is 'the safety of goods', answered by $56.5\%$ of respondents. The respondents are generally not satisfied with babies' cosmetics. So, a baby's skin is threatened by a newly-built house syndrome, the increase of atopic dermatitis, etc., caused by an environmental pollutions, a change of diet and a change of residential life. Under these actual conditions, babies' cosmetics which can protect a delicate and sensitive skin of a baby should be developed immediately. Consumers should have a correct choice with precise recognition and information on a baby's skin and cosmetics and continually use the efficacious and excellent babies' cosmetics to prevent a baby from a skin irritation, and need to show a keen interest in a healthy skin of a baby.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.136-147
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• 2009

Statement of problem: Since the introduction of the concept of osseointegration in dental implants, high long-term success rates have been achieved. Though the use of dental implants have increased dramatically, there are few studies on domestic implants with clinical and objective long-term data. Purpose: The aim of this retrospective study was to provide long-term data on the $Implantium^{(R)}$ implant, which features a sandblasted and acid-etched surface and internal connection with microthreads. Material and methods: 106 $Implantium^{(R)}$ implants placed in 38 patients at Yonsei University Hospital were examined to determine the effect of various factors on implant success and marginal bone loss, through clinical and radiographic results during a 6 to 30 month period. Results: 1. Out of a total of 106 implants placed in 38 patients, one fixture was lost, resulting in a 99.1% cumulative survival rate. 2. Among the 96 implants which were observed throughout the study period, the survival rates were 97.0% in the maxilla and 100% in the mandible. The survival rate in the posterior regions was 98.9% and 100% in the anterior regions. 3. The mean bone loss during the first year after prosthesis placement was 0.17 mm, while the mean annual bone loss after the first year was 0.04 mm, which was statistically less than during the first year(P<.05). 4. There was no significant difference in marginal bone loss according to age during the first year(P>.05), but after the first year, the mean annual bone loss in patients above 50 years was significantly greater(P<.05) compared with patients under 50 years. 5. No significant difference in marginal bone loss was found according to the following factors: gender, jaw, location in the arch, type of implant(submerged or non-submerged), presence of bone grafts, type of prostheses, and type of opposing dentition(P<.05). Conclusion: Based on these results, the sole factor influencing marginal bone loss was age, while factors such as gender, jaw, location in the arch, type of implant, presence of bone grafts, type of prostheses and type of opposing dentition had no significant effect on bone loss. In the present study, the success rate of the $Implantium^{(R)}$ implant with a SLA surface and internal connection with microthreads was satisfactory up to a maximum 30 month period, and the marginal bone loss was in accord with the success criteria of dental implants.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.65-72
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• 2010

General anesthesia has been researched and developed in dentistry as on type of management technique to sedate patients who may be uncontrollable or require medical consideration. There has been continuous research into this area, but analysis of large set of patients over a sustained period of time is lacking. Thus, this study analyzes the records of patients who received general anesthesia at the Yonsei University Dental Hospital Department of Pediatric and Clinic for the Disabled. 1. Patient's age ranged from 1 to 66, with under 5 being the largest group with 410 members(38.5%). The study included more men than women, with 695 male members(65.3%). 2. Type of dental procedure performed were as follows(per person) : 5.6 Dental restoration; 2.3 Endodontic treatment of deciduous and primary teeth; 2.5 preformed crowning; and 1.6 extractions. Procedures took an average of 100 minutes. 3. 1022 patients(95.9%) received dental care under general anesthesia once and 43 patients(4.1%) received dental care under general anesthesia two or more times. Dentistry under general anesthesia has the many benefit. However, without appropriate post-treatment care, it is difficult to maintain good oral health. Therefore, it is important to improve the efficiency and safety of general anesthesia through future research.

• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.73-84
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• 2015

In this research, two careers connectable with the contents of the curriculum of fifth to sixth grade elementary school students were selected among other promising future careers in biotechnology and medical engineering fields. 'Design-based promising future career STEAM program' was developed and its validity and effectiveness were verified. Reflecting recent issues, and complying with the STEAM standard (frame) instructional materials were developed through group deliberations for nine months, based on the achievement standards through an analysis of subject curriculum revised in 2009. This was prepared so that students are able to experience biotechnology and medical engineering related careers in a simulational form emphasized with creative design to make them prefer natural sciences and engineering careers and draw their interests and recognition of the relevant careers under the two disciplines. As a result of such application to STEAM Leader School students at the verification stage of the program, the contents and level of the program were verified suitable, receiving favorable reviews. And as a result of applying the developed program on other elementary school students, it was discovered that significant improvements were found in their career consciousness. Through this research, it was suggested that there is a need for a simplification of the curriculum content standards, a provision of 'standard for integration,' development of teachers' ability in reconstituting or organizing the STEAM and proceeding classes, continuous long-term support to see the effects of a policy or a program, and a reinforcement of career education integrated in the curriculum.

• Food Science and Preservation
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• v.16 no.5
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• pp.650-655
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• 2009

This study was conducted to measure the quality characteristics of rough rice during low temperature drying by using an experimental dryer and heat pump with a capacity of 150kg at four temperature levels of 20, 30, 40, and $50^{\circ}C$. The quality and proper drying temperature of rough rice was investigated by measuring variations in moisture content, crack rates, germination rates and cooked rice. Temperatures over $40^{\circ}C$ is considered a high-temperature area, and below $40^{\circ}C$ is considered a low-temperature area. The drying rates were 0.3, 0.6, 0.9, and 1.3%/hr, and the crack ratios were 0, 1.6, 6.8, and 24.2% at the drying temperatures of 20, 30, 40, and $50^{\circ}C$, respectively, which showed that the higher the drying temperature was, the higher the drying rate and crack rate was. Therefore, 20 and $30^{\circ}C$ were found to be appropriate drying temperatures for avoiding crack formation, and $50^{\circ}C$ was inappropriate. At $40^{\circ}C$, the operation methods needed to be modified to limit cracking, such as increasing the tempering time. Also, as the drying temperature increased, the germination rate decreased. Germination rates at 20 and $30^{\circ}C$ were suitable for using the rough rice as a seed, and those at 40 and $50^{\circ}C$ were over 80%, which is the minimum allowable percentage. In the sensory evaluation of cooked rice, the quality of appearance, taste, and texture varied as a function of drying temperature. When considering these factors, the cooked rice that was dried at 20 and $30^{\circ}C$ was better than the cooked rice dried at high-temperature. Consequently, in view of drying temperature and rates, the best conditions for drying rough rice were below $30^{\circ}C$ and below 0.6%/hr.