• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.117-123
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• 1968

A simplest and best method to find out lime requirement for Korean soils is described. Twenty six top soil samples were collected from various localities and chemical characteristics were dertermined. Three different buffer curve methods were employed as the standard to find out the most reliable test for lime requirement. In addition, the lime requirement test by the Shoemaker's and Woodruff's as well as the O.R.D. kit method were compared with the most reliable buffer curve method. The results may be summarized as follows. 1. The regression equation of the most reliable lime requirement by buffer curve method, y, on percent base saturation of various soils, X, was y=9.69-0.106 X and the negative correlation coefficient r=-0.84 was statistically significant at 5% level. 2. Lime requirement test by the best, buffer curve, method was more well correlated with the sum of exchangeable hydrogen and exchangeable aluminum contents of the soil samples than the exchangeable hydrogen content only. 3. The ordinary buffer curve method for lime requirement is more reasonable than the lime requirement test by the buffer curve prepared after addition of 1 normal potassium chloride or calcium chloride solutions. 4. The lime requirement tests by the most reasonable buffer curve method, X, and by the Woodruff's, the Shoemaker's and O.R.D. kit were compared. The best method for laboratory lime requirement test was the Shoemaker's method and the O.R.D. kit method also was good enough for the field test and these two method are recommended as the unified method of lime requirement test in each soil testing laboratories throughout Korea.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.1
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• pp.25-34
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• 2019

Objectives : This study aimed to compare the psychosocial characteristics among patients with functional gastrointestinal disorder (FGID), adults with functional gastrointestinal symptoms, and normal control group and investigate factors related to quality of life (QoL) of FGID patients. Methods : 65 patients diagnosed with FGID were selected. 79 adults were selected as normal control group based on the Rome III diagnostic criteria, and 88 adults who showed functional gastrointestinal symptoms were selected as "FGID positive group". Demographic factors were investigated. Psychosocial factors were evaluated using the Korean-Beck Depression Inventory-II, Korean-Beck Anxiety Inventory, Korean-Childhood Trauma Questionnaire, Multi-dimensional Scale of Perceived Social Support, Connor-Davidson Resilience Scale and WHO Quality of Life Assessment Instrument Brief Form. A one-way ANOVA was used to compare differences among groups. Pearson correlation test was used to analyze correlations between QoL and psychosocial factors in patients with FGID. Results : There were group differences in the education level. Depression (F=29.012, p<0.001), anxiety (F=27.954, p<0.001) and Childhood trauma (F=7.748, p<0.001) were significantly higher in FGID patient group than in both FGID-positive and normal control group. Social support (F=5,123, p<0.001), Resilience (F=9.623, p<0.001) and QoL (F=35.991, p<0.001) were significantly lower in the FGID patient group than in others. QoL of FGID patients showed a positive correlation with resilience (r=0.475, p<0.01), and showed a negative correlation with depression (r=-0.641, p<0.01), anxiety (r=-0.641, p<0.01), and childhood trauma (r=-0.278, p<0.05). Conclusions : FGID patients have distinctive psychosocial factors compared to the both FGID-positive and normal control group. Therefore, the active interventions for psychosocial factors are required in the treatment of patients with FGID.

• Journal of Fisheries and Marine Sciences Education
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• v.14 no.2
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• pp.177-190
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• 2002

An experimental study was carried out to make clear heat transfer characteristics in flow boiling of binary mixtures of refrigerants R134a and R123 in a uniformly heated horizontal tube. Experiments were run at a pressure of 0.6 MPa both for pure fluids and mixtures in the ranges of heat flux $10{\sim}50{kW/m}^2$, vapor quality 0~100% and mass flux 150-600 $kg/m^2s$. Heat transfer coefficients of mixtures were reduced compared to the interpolated values between pure fluids both in the low quality region where the nucleate boiling is dominant and in the high quality region where the convective evaporation is dominant. Total pressure drop during two-phase flow boiling in a horizontal tube consists of the sum of two components, that is, the frictional pressure drop and pressure drop due to acceleration. The frictional pressure drop is the most difficult component to predict, and makes the most important contribution to the total pressure drop. On the other hand, the acceleration pressure drop resulting from the variation of the momentum flux caused by phase change is generally small as compared to the frictional pressure drop. There is no significant difference in measured pressure drop between mixtures and pure fluids. The correlation of Martinelli and Nelson predicted most of the present data both for pure and mixed refrigerants within 30%.

• Journal of the Korean Society for Heat Treatment
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• v.29 no.3
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• pp.113-123
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• 2016

In the present work, we investigated the effects of the carbon potential on the formation of carbide at the carburized surface and anti-pitting fatigue strength in the supercarburized steels. Two low carbon steels with different Cr concentrations were adopted and the repeated supercarburizing treatment carried out with the different carbon potential conditions. The microstructure and carbides at the supercarburized surface were observed by using optical microscope and scanning electron microscope. The microhardness test was performed and the hardness distribution and the effective case depth at the supercarburized surface were discussed. The roller pitting fatigue test was carried out and the fatigue strength was evaluated with different the carbon potential conditions. The microstructure of the fatigue specimen surface was observed by means of scanning electron microscope and scanning transmission electron microscope. Depending on the chemical composition of the steels and the carbon potential condition, the resistance of temper softening and pitting failure was influenced due to the carbide distribution and the formation of coarse network carbide. Thus, it was confirmed that the control of the carbide formation is a key factor to improve the anti-pitting fatigue strength in the supercarburized steels.

• The Journal of Advanced Prosthodontics
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• v.12 no.3
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• pp.114-123
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• 2020

PURPOSE. The aim of this study was to evaluate the corrosion resistance of the specimens produced by five different commercial metal laser sintering (MLS) systems with their recommended Co-Cr alloy powders. MATERIALS AND METHODS. The MLS machines and the alloy powders used were, ProX 100-ST2724G (St-Pro), Mysint 100-EOS SP2 (SP2-Mys), EOSINT 270-EOS SP2 (SP2-EOS), SLM 100-Starbond CoS (SB-SLM), and MLab Cusing-Remanium^® Star (RS-MLab), respectively. Eight specimens from each group were prepared. Open circuit potential (E_ocp) and electrochemical impedance spectroscopy (EIS) measurements of polished surfaces of the specimens were conducted in a three-electrode cell using a potentiostat-galvanostat in Fusayama-Meyer artificial saliva (AS). Specimens from each group were immersed in AS and de-ionized water for seven days. E_ocp, charge transfer resistance (R_ct) values, and released ions (㎍/㎠ × 7d) in different solutions were determined. The specimen surfaces were observed with SEM/EDS. Results were analyzed statistically. RESULTS. E_ocp values have shifted to potentials that are more positive over time. Steady-state E_ocp values were from high to low as follows, SB-SLM, SP2-Mys, SP2-EOS, RS-MLab, and ST-Pro, respectively. After 60 mins, RS-MLab specimens had the highest R_ct value, followed by SP2-Mys, SB-SLM, SP2-EOS, and ST-Pro. In all groups, ion release was higher in AS than that in de-ionized water. CONCLUSION. There were small differences among the corrosion resistances of the Co-Cr alloy specimens produced with MLS systems; meanwhile, the corrosion resistances were quite high for all specimens.

• Research in Community and Public Health Nursing
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• v.15 no.3
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• pp.376-384
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• 2004

Purpose: The CHP program has been evaluated as one of the most successful program in the public health area in Korea. The objects of this study were as follows: 1) to evaluate the job activities of the CHP program, using service contents analysis. 2) to figure out personal factors and the outcome of CHP's activities. Method: Data were collected by sending questionnaires to 130 subjects through the mail from May to December 2003. The response rate was 48.0%. The Data were analyzed by the SPSS WIN program with t test and Pearson correlation coefficient. In using these methods. independent variables are CHP's personal factors (age, experience, certification of specialty) and regional factors (geographical classification, aged population, village workers, cooperation of community leaders, work-conditions), and a dependent variable is the outcome of CHP's job activities. Result: The results of t test analysis show that regional differences between factors are influential in the welfare service, the routine job, and the consultation. As a whole, this is shown that CHPs represent experience, the number of village workers and CHPs living condition of work and most of the categories of jobs that influenced over statistical meaning of differences (t=2.417, p=1.043, t=6.123, p=.004, t=4.309, p=.000). There is a significant positive relation between the routine job and the consultation(r=.455, p=.000), the consultation and the education(r=.461, p=.000). Conclusion: Finally, according to the results of this study, the CHP program should be developed and continue to meet the basic health care needs of the residents in accordance with the philosophy of their own primary health care.

• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.21-28
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• 2001

Enzyme linked-immunosorbent assay (ELISA) for a rapid detection of fungi, Aspergillus and Penicillium genera in food, were developed and their efficiencies were approved by detecting artificially contaminated agricultural commodities. Mice were immunized with partially purified Aspergillus flavus extracellualr polysaccharide (EPS) and lymph node cells of the mice were fused with the myeloma cells for production of monoclonal antibodies. Mab 1G11, one of the antibodies, was selected and purified. A sandwich ELISA was established and its detection limit toward A. flavus EPS was 1mg/ml. Among the 59 strains tested (including 18 species of Aspergillus, 16 of Penicillium, 11 of Fusarium, 1 of Absidia, 2 of Alternaria, 2 of Candida, 2 of Cladosporium, 2 of Geotrichum, 2 of Mucor, 2 of Rhizopus, 1 of Trichoderma), species of Aspergillus and penicillium had a high reactivity with Mab 1G11 even up to 10,000 times dilution of culture broths. The other genera except Cladosporium resinae showed no reactivity, thus Mab 1G11 was specific to the genera of Aspergillus and Penicillium. The epitope of A. flavus EPS against monoclonal Mab 1G11 was on the carbohydrate moiety when 1 to 100$\mu g/g$ A. flavus EPS were put into rice, potato, and mandarin orange, the average recoveries detected by sandwich ELIA were 123, 59, and 76%, respectively. Correlation was found to be linear between the EPS, and mycelium of A. flavus and Penicillium citrinum grown in a liquid medium (r=0.87 and 0.96), and also between the EPS and colony forming unit in solid media of rice of potato (r=0.91-0.99).

• Natural Product Sciences
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• v.10 no.3
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• pp.119-123
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• 2004

The effects of BHSH on L-DOPA-induced increase in dopamine content in PC12 cells were investigated. L-DOPA treatment at $20\;or\;50\;{\mu}M$ increased dopamine content after both 24 and 48 h of incubation in PC12 cells. However, the co-treatments of BHSH $(10-50\;{\mu}M)$ with L-DOPA $(20\;or\;50\;{\mu}M)$ significantly inhibited the increase of dopamine content induced by L-DOPA. BHSH treatment at $10-50\;{\mu}M$ significantly inhibited basal aromatic L-amino acid decarboxylase (AADC) activity in a concentration-dependent manner at 15 min, and then AADC activity was rapidly recovered to the control level at about 2 h. These results indicate that the inhibition of AADC activity by BHSH was, in part, contributed to the early-stage decrease of dopamine content induced by LDOPA in PC12 cells. Taken together, it is proposed that the short-term inhibition of dopamine biosynthesis by BHSH was mediated by the regulation of tyrosine hydroxylace (TH).

• Journal of Korean Academy of Nursing
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• v.23 no.1
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• pp.5-15
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• 1993

This study examined the effects of therapeutic communication skills, self esteem and self concept, psychiatric nursing lectures on students' psychiatric nursing practice evaluation scores. The purposes of this study were to determine factors influencing students' psychiatric nursing practice to improve the quality of that practice. The subjects were 123 third year nursing students in the department of nursing of G University in C city. Data were collected from 1989 to 1991 by question-aires and academic records. Pearson Correlation and t-test were used in analysing the data to confirm the relationship and influence among the study variables. Stepwise Multiple regression was used to confirm the predictors of the nursing students' psychiatric nursing practice evaluation scores. The results were as follows : 1) Relationship of General characteristics and Psychiatric Nursing Practice Evaluation Scores : General characteristics were not significant on psychiatric nursing pracice evaluation scores. 2) Relationship of the therapeutic communication skill and psychiatric nursing practice evaluation scores : the higher the degree of therapeutic communication skill was the higher the scores for psychiatric nursing practice (r=.5528, p(.001). 3) Relationship of psychiatric nursing course and psychiatric nursing practice evaluation scores the higher the scores in the psychiatric nursing course the higher the scores for psychiatric nursing practice (r=.2793, p(.01). 4) Relationship of self-esteem & self concept and psychiatric nursing practice evaluation scores : Self-esteem 8f concept was not significant on psychiatric nursing practice evaluation scores. 5) Stepwise multiple correlation of therapeutic communication skills, self-esteem and self concept, psychiatric nursing lectures on psychiatric nursing practice evaluation scores showed that therapeutic communication skills and the psychiatric nursing course scores influenced the evaluation scores psychiatric nursing practice significantly.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.1
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• pp.3-13
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• 1993

This study was conducted at seven degreasing processes in plating plants located in Seoul, Incheon, Ansan, and Taejeon areas from July 21 to august 27, 1992. This study was performed to assess the TWA exposures to trichloroethylene (TCE) and evaluate factors affecting TCE concentrations in degreasing process. Two-Point Eddy Diffusional Model suggested by Wadden et al. was employed to calculalte emission factors according to degreaser type. Results are summarized as follows. 1. The TWA exposures of the degreasing operators ranged from 1.4 ppm to 123 ppm, and those of three plants out of seven were exceeding 50 ppm of both the Korean and U.S. OSHA standards. Degreasing assistant of Plant B, was exposed to 59 ppm. 2. The average concentrations at the distance 0, 1.5, 3.0 m from the degreasers were 1.014, 24, and 18 ppm, respectively, and showed a signifficant difference by distance (p<0.01). 3. The emission of TCE was reduced by installing local exhaust systems, condensers, and refrigeration lines at the degreasers (p<0.01). 4. The major factors related to exposure of operators were workload (r=.9621. p<0.01) and dimensions of degreansing room(r=-.8667, p<0.05). 5. If the air in degreasing room is mixed violently by other factors in addition to diffusion, the emission factors can not be evaluated because the important hypothesis of the Two-Point Eddy Diffusional Model can not be accepted. 6. The ultrasonic degreaser without the local exhaust ststem, condenser, and refrigeration lines emitted TCE three times greater than the ultrasonic degreaser with condenser and refrigeration 1ines only.