• Journal of Biosystems Engineering
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• v.1 no.1
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• pp.1-6
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• 1976

This paper is the third one of the study on balanced type oscillating mole-drainer, the first one was presented in No 9. Gyeongsang College Report and the second one in Vol. 17, No.4 of the KSAE. In the first part of this study, the characteristics of traction forces between the nonoscillating earth working equipments and oscillating ones was compared. A model of the balanced type oscillating mole-drainer, which composed of a mechanism that may reduce the machine vibration, was designed following the dimensional analysis and similitude technique. The model test was carried out to clarify the balancing mechanism of the oscillating parts and other parts of the machine. In the light of the results from the model tests, a prototype machine was made for experimental purpose. Results from the field test by a reported in the near future. In the second report, the model tests were carried out under the same soil conditions, i.e, . oscillating frequency, running velocity, and oscillating amplitude, etc. It was clear that use of balanced type oscillating model could substantially reduce the vibration of the whole system of the machine, when compared with the nonoscillating type model. In this paper(the third report), results of investigation on the traction force, power requirement, and moment. etc, is presented. Analysis of variance technique was used for analyzing the effect of the frequency, amplitude, and running velocity on the draft force, torque, power requirements, and moments. The results obtained from the model tests are as follows, 1) By practicing a balanced-type oscillating mole-drainer, it was possible to reduce the traction resistance by 55.1-61. 2 percent of traction resistance, however, was 1.75 - 1.95 times greater than the value of resistance which was induced by use of a mole-drainer with single bullet. The resistance of rear shank against soil was considered as a main causing factor of the above results. 2) As the oscillation frequency was increased, the traction resistance was decreased. Considering on the effect of oscillation the greater the amplitude, and the slower the running velocity was, the greater the reduction ratio of traction resistance was. 3) The ratio of the traction resistance of oscillating mole-drainer to that of non-oscillating one could be represented as a function of dimensionless variable (V/$Af$). The results from the tests were well agreed with the reported results from the experim ents on oscillation plow or hoe. 4) By taking a lower value of (V/$Af$), reducing the traction resistance was possible. This fact meant, however, that the efficiency of mole drain practice would be lower. 5) It was experimentally confirmed under the same condition of soil that the variable (R/$rD1^3$) could be represented as a function of a variable($V^2/gD$) when a non\ulcornerocillating mole-drainer was used. 6) When a oscillating mole-drainer was used, the variable(R/$rD_1^{3}$) could be represented as a function of two variables ($v^2/gD_1$) and (V^2/gD_1$). 7) The torque was not affected by a change of frequency. However, a relation of proportionality existed between torque and amplitude, running velocity, and ratio of bullet diameter. When a balanced type oscillating mole-drainer with two bullets was used, torque was increased by 52.8-78. 4 percent and total power requirement was also increased. 8) Total power requirement was increased linearly in accordance with the increasing frequency, 41.96 percent of total power was used for oscillating action. The magnitude of total power requirement was 1. 8-9. 4 times greater than that of a non-oscillating mechanism. In the view point of power requirement, it was not advisable to increase the frequency, amplitude, running velocity, and ratio of bullet diameter at the same time. 9) Only the positive moment occured in the rear shank. Change of the diameter of a rear bullet, could not affect the balancing against the soil resistance. It was necessary for rear bullet to have a large resistance against soil only when the rear bullet was in backward motion. 10) Within an extent of the experimental base, optimum limits for several design factors were A=0.5cm, $f$=22.5Hz, V=O. 05m/sec, and $\lambda$=1.0 By adapting these values traction resistance was reduced by 40 percent and vibration acceleration wa s reduced by 60 percent. Even though the total , power requirements for operating a balanced type oscillation mechanism was greater ~than that of non-oscillating one, using a oscillating mechanism would be more effective. Because a balanced type oscillating mechanism is used, tractive resistance will be reduced and then the lighter . tractive equipment could be used.

• Journal of Life Science
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• v.20 no.6
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• pp.811-818
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• 2010

Optimal agitation speed and aeration rate for the production of gellan by Sphingomnas paucibilis NK2000 in a 7 l bioreactor were found to be 400 rpm and 1.0 vvm. The best time for glucose feeding into the medium for enhanced production of gellan by S. paucibilis NK2000 was 36 hr after cultivation. The concentrations of gellan produced by S. paucibilis NK2000 from 1) 20.0 g/l glucose without additional feeding, 2) 20.0 g/l glucose with feeding of 200.0 g/l glucose at 36 hr, in which the final concentration in the medium was 10.0 g/l, 3) 20 g/l glucose with feeding of 200.0 g/l glucose and a shift in an agitation speed from 400 to 600 rpm, 4) 20.0 g/l glucose with feeding of 200.0 g/l glucose at 36 hr and shifts in an agitation speed from 400 to 600 rpm and an aeration rate from 1.0 to 1.5 vvm, 5) and 20.0 g/l glucose with feeding of 200.0 g/l glucose at 36 hr and shifts in an agitation speed from 400 to 600 rpm and an aeration rate from 1.0 to 2.0 vvm, were 5.19, 5.74, 6.73, 7.93, and 9.40 g/l, respectively, and their conversion rates from glucose were 26.0, 19.1, 22.4, 26.4, and 31.3%, respectively. Compared to those developed using a normal process, production of gellan by S. paucibilis NK2000 from 20.0 g/l glucose was 1.81 times higher, and and its conversion rate was 1.20 times higher when the optimized process developed in this study was used.

• Journal of Life Science
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• v.23 no.4
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• pp.542-553
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• 2013

The aim of this work was to establish the optimal conditions for the production of cellobiase by a marine bacterium, Cellulophaga lytica LBH-14, using response-surface methodology (RSM). The optimal conditions of rice bran, ammonium chloride, and the initial pH of the medium for cell growth were 100.0 g/l, 5.00 g/l, and 7.0, respectively, whereas those for the production of cellobiase were 91.1 g/l, 9.02 g/l, and 6.6, respectively. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}_{7H2}O$, and $(NH_4)_2SO_4$ for cell growth were 6.25, 0.62, 0.28, and 0.42 g/l, respectively, whereas those for the production of cellobiase were 4.46, 0.36, 0.27, and 0.73 g/l, respectively. The optimal temperatures for cell growth and for the production of cellobiase by C. lytica LBH-14 were 35 and $25^{\circ}C$, respectively. The maximal production of cellobiase in a 100 L bioreactor under optimized conditions in this study was 92.3 U/ml, which was 5.4 times higher than that before optimization. In this study, rice bran and ammonium chloride were developed as carbon and nitrogen sources for the production of cellobiase by C. lytica LBH-14. The time for the production of cellobiase by the marine bacterium with submerged fermentations was reduced from 7 to 3 days, which resulted in enhanced productivity of cellobiase and a decrease in its production cost. This study found that the optimal conditions for the production of cellobiase were different from those of CMCase by C. lytica LBH-14.

• Journal of Korean Academy of Nursing
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• v.22 no.1
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• pp.49-67
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• 1992

Most hospitalized children will experience physical pain as well as psychological distress. Preschool children's pain perception related to painful procedures can increase due to elevated anxiety and fear because they do not have understanding logical of their disease and hospitalization. In particular, they are distressed about needle - related procedures which are feared because they are seen to be a cause of bodily damage. This descriptive study attempted to identify pain perception levels in preschool children and their mothers. A self-reporting measurement and behavioral observation were used to collect the data. A total of 25 hospitalized preschool children and their mothers were investigated and data were collected about 60 painful procedures. Data collection was carried out by the researcher and two trained investigators from November first to December tenth. Three insruments were used to collect the data : Faces Pain Rating Scale(FPRS) developed by Beyer was used to measure the degree of preschool children's pain perception about painful procedures. The Visual Analogue Scale(VAS) devised by Huskisson was used to assess the degree of mothers' pain perception about their children's painful procedures. A Pain Behavioral Checklist based on the Procedure Behavior Check List by LeBaron and Zelter and modified by the researcher was used to observe behaviors of preschool children, their mothers, and nurses when the painful procedures took place. The data were analyzed by an SPSS program, and were tested using real numbers, percentages, Pearson correlation coefficient, t-test, and ANOVA. The results of this study are as follows : 1. Of all the painful procedures, the mean score for the FPRS for the preschool children's pain perception was 4.02 points, and the mean score for the VAS of mothers' pain perception was 10.92 points. 2. A Positive correlation which was statistically significant was found between the pain perception of preschool children and their mothers (r＝.53, p＜.01). that is, the higher the children's pain perception was, the higher their mothers' pain perception was. 3. The characteristics of the painful procedures related with children's pain perception as follows : The type of painful procedure was found to be statistically significant (F＝23.44, p＜.01), Among the three procedures Ⅳ starting was found to be perceived as the most painful procedures to the children. The greater the number of times that the procedure had been done, the higher the pain perception was (F＝4.44, p＜.01), and the longer the duration of the procedure, the higher the pain perception wa(r＝.30, p＜.05). Pain perception in the treatment room was higher than in the children's room(t＝6.30, ＜.01), pain perception in the mother's presence was the higher than when the mother was not present (t＝2.91, p＜.01). 4. The characteristics of the painful procedures related with the mothers' pain perception as follows : The type of painful procedure was found to be statistically significant(F＝6.01, p＜.01). Among the three procedures Ⅳ sampling was found to be perceived as the most painful procedures to the mothers. The greater the number of times that the procedure had been done, the higher the pain perception was (F＝5.95, p＜.01), and the longer the duration of the procedure, the higher the pain perception was (r＝.31, p＜.05). Pain perception in the treatment room was higher than in the children's room (t＝3.51, p＜.01), but pain perception in the mother's presence showed statistically significant no difference. 5. Of all of the 19 children's behaviors during the painful procedures, the most frequent behaviors observed Were as follows in order of frequency “crying”, “screamirig”, “facial grimacing”, “physical resistance”, Of all of the nine methers' behaviors, the most frequent by observed in “console children”, “hold children”, “applaud children”, Of all of the 11 nurses' behaviors during the painful procedures, the mast frequent in order were “smiling”, “physical restraint”, “console children”, “praise children”. 6. A positive correlation between children's and mothers' pain perception and children's behaviors was found to be statistically significant (r＝.65, p＜.01, r＝67, p＜.01). Also the relationship between children's and mothers' pain percertion, and mothers' behavior was found to be statistically significant (r＝.57, p＜. 01, 4＝.60, p＜.01). The relationship between children's pain perception and nurses' behaviors was also found to be statistically significant (r＝.46, p＜.01), but there was difference between mothers' pain perception and nurses' behaviors.

• Tuberculosis and Respiratory Diseases
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• v.50 no.1
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• pp.42-51
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• 2001

Background : Recently, cardiopulmonary exercise testing (CPX) has become a popular diagnostic method for differentiating the main cause of exertional dyspnea or exercise limitation. We evaluated the difference in the CPX results according to interpretative algorithms and the methals of exercise in Korea. Method : Sixty-six patients with chronic lung disease and 48 adults with dyspneic symptoms, but with no abnormalities in a spirometry performed symptom limited CPX, were included in this study. The results were interpreted using both Wasserman's(WA) and Eschenbacher's algorithm (EA), and a comparison between both algorithms was made. Thirty-three healthy medical students performed the CPX with a cycle ergometer and treadmill. The results were interpreted with EA and the concurrence in interpretations was evaluated accord ing to the methods of exercise. Results : 1. In patients with chronic lung disease, the overall concordance rate between the two algorithms was 63.6%. The concordance rates waw 69.8% in patients with obstructive, 25.0% in those with restrictive, and 66.7% in those with mixed pulmonary insufficiency. In patients with dyspneic symptoms but normal findings in resting spirometry, the concordance rate was 60.4%. 2. In healthy medical students, in results inter preted with EA, the concordance rate between the cycle ergometer and treadmill exercise was 25.0%. Conclusion : Both interpretative algorithms and methods of exercise may affect the CPX results. In using CPX as a diagnostic test for the causes of dyspnea in the Korean population. the interpretative algorithms and method of exercise need to be standardized, and a predictive $VO_2$max equation needs to be established.

• Journal of Life Science
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• v.22 no.10
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• pp.1295-1306
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• 2012

A microorganism producing carboxymethylcellulase (CMCase) was isolated from seawater and identified as Bacillus atrophaeus. This species was designated as B. atrophaeus LBH-18 based on its evolutionary distance and the phylogenetic tree resulting from 16S rDNA sequencing and the neighbor-joining method. The optimal conditions for rice bran (68.1 g/l), peptone (9.1 g/l), and initial pH (7.0) of the medium for cell growth was determined by Design Expert Software based on the response surface method; conditions for production of CMCase were 55.2 g/l, 6.6 g/l, and 7.1, respectively. The optimal temperature for cell growth and the production of CMCase by B. atrophaeus LBH-18 was $30^{\circ}C$. The optimal conditions of agitation speed and aeration rate for cell growth in a 7-l bioreactor were 324 rpm and 0.9 vvm, respectively, whereas those for production of CMCase were 343 rpm and 0.6 vvm, respectively. The optimal inner pressure for cell growth and production of CMCase in a 100-l bioreactor was 0.06 MPa. Maximal production of CMCase under optimal conditions in a 100-l bioreactor was 127.5 U/ml, which was 1.32 times higher than that without an inner pressure. In this study, rice bran was developed as a carbon source for industrial scale production of CMCase by B. atrophaeus LBH-18. Reduced time for the production of CMCase from 7 to 10 days to 3 days by using a bacterial strain with submerged fermentation also resulted in increased productivity of CMCase and a decrease in its production cost.

• Journal of Life Science
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• v.21 no.9
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• pp.1205-1213
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• 2011

The optimal concentrations of salts in medium for cell growth and the production of carboxymethylcellulase (CMCase) by a recombinant E. coli JM109/DL-3 were established using two statistical methods: orthogonal array method (OAM) and response surface method (RSM). The analysis of variance (ANOVA) of data based on OAM indicated that $K_2HPO_4$ gave maximum sum of square (S) and percentage contribution (P) for cell growth as well as production of CMCase. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$, and $(NH_4)_2SO_4$ in medium for cell growth extracted by Qualitek-4 (W32b) Software were 10.0, 1.0, 0.2, and 0.6 g/l, respectively, whereas those for the production of CMCase by E. coli JM109/DL-3 were 5.0, 1.0, 0.4, and 0.6 g/l. The analysis of variance (ANOVA) resulting from RSM indicated that a highly significant salt for cell growth was $K_2HPO_4$ ("probe>F" less than 0.0001), whereas $K_2HPO_4$ and $MgSO_4{\cdot}7H_2O$ were significant for the production of CMCase. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$, and $(NH_4)_2SO_4$ for cell growth extracted by Design Expert Software were 7.44, 1.08, 0.22, and 0.88 g/l, respectively, whereas those for production of CMCase were 5.84, 0.69, 0.28, and 0.54 g/l. The optimal concentrations of salts and their influences on cell growth and production of CMCase extracted by OAM were almost the same as those by RSM. Production of CMCase by a recombinant E. coli JM109/DL-3 under optimized concentration of salts was 1.93 times higher than that by Bacillus amyloliquifaciens DL-3.

• Journal of the Korean Geographical Society
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• v.52 no.1
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• pp.25-53
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• 2017

The ultimate goal of this research is to examine the geographical characteristics of therapeutic spaces where have been appeared in Wa-dong and Gojan-dong, Ansan-si after the disaster of the MV Sewol. As looking into the inside, the aim of the therapeutic spaces, which cover each target group (victims) individually, is various and different because the disaster of the MV Sewol generated various direct and indirect victims requiring healing. The therapeutic spaces are estimated at about 10 organizations and are leaded by private agents predominantly. Furthermore, the therapeutic spaces are located near, but are aside from Danwon high school where many students are reported killed and injured in the incident. And the therapeutic spaces provide simple and repetitive diversions, for example, having a meal, knitting and studying, rather than special programs to restore a broken daily life to the original state. On the basis of such a background, the geographical characteristics of the therapeutic spaces related to the disaster of the MV Sewol can be summarized as follows; first, it seems that target groups accept the therapeutic spaces as the concept of place gradually. Even though most of the therapeutic spaces were suggested by third parties at first, target groups are involved in the management and recollection of their own therapeutic spaces as well as the plan for a future direction now; and consider the therapeutic spaces as exclusive properties. Second, the disaster of the MV Sewol have embedded collective trauma to not only direct victims, but extensive groups such as parents, brothers and sisters, relatives, friends and neighbors as noted earlier. Therefore, the therapeutic spaces support comprehensive target groups; but each therapeutic space is not overlapped each other. However, to solve collective trauma in a local community effectively, the therapeutic spaces are networked closely and build a regular cooperative system. Third, a continuous memory is mentioned as an important point to overcome collective trauma, but some phenomena such as fatigue and conflict with neighbors, out-migrants and a faded atmosphere as time passes act as risk factors in Ansan-si. To keep a continuous memory, the therapeutic spaces attempt the recovery of local communities and devise various events, for example, cultural performances; furthermore, are closely connected with external organizations.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.145-151
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• 2002

The effect of low pH on physiological changes was studied with the acidophilic green alga, Clamydomonas acidophila, UTCC 122. The growthrates (${\mu}$) were identical, $0.5{\sim}0.7\;day^{-1}$, at pH 3.7${\sim}$6.7 and no significantly different (ANOVA, p =0.134), showing cell volume reduced gradually as they were growing, whereas that at pH 2.7 was falling to zero and cell volume increased dramatically. Chlorophyll a concentration of the cultures incubated for one day was $191{\sim}255\;pg\;cell^{-1}$, after then it declined from $60{\sim}103\;pg\;cell^{-1}$ at pH 3.7${\sim}$6.7 except $210\;pg\;cell^{-1}$ at pH 2.7, which was directly related with cell volume. External carbonic anhydrase (CA) activity was varied from1.1 to$3.7{\times}10^{-4}\;E.U.\;mm^{-2}$, showing the gradualincrease during culture, except at 2.7 and pH 5.7. However there was not found any relationship among the pH gradient cultures. CA molecular mass of C. acidophila was 29 kBa, and concentration of that was identical in all cultures. The proteins of 41 kDa and 63 were not or very　faintly expressed in low pH cultures, in contrast that of 17 kDa more expressed. In this work, we found that C. acidophila could live optimally within a wide range of acidic pH, and 17 kDa of unidentified protein might be concerned with tolerating in low acid environment.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.349-356
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• 2005

For the purpose of making a new type of functional drinkable yoghurt, skim milk containing $0.5\~2.0\%$(w/v) green tea powder was fermented by the mixed stains of Streptococcus thermophilus and Lactobacillus acidophilus. Quality characteristics of the drinkable yoghurts were evaluated in terms of quality-keeping properties(number of viable cells, pH, titratable acidity) and sensory properties. When the drinkable yoghurts added with $0.5\~2.0\%$ green tea powder were kept at $4^{\circ}C\;and\;20^{\circ}C$ for 20 days, the number of viable cell counts of the lactic acid bacteria($2.1\times10^8\~6.2\times10^8$ CFU/mL). pH($4.16\~4.22$) and titratable acidity($0.792\~0.881\%$) were not significantly changed for all drinkable yoghurts during the storage at $4^{\circ}C\;and\;20^{\circ}C$ days, but the number of viable cell counts($4.2\times10^3\~1.8\times10^5$ CFU/mL), pH($3.82\~3.92$) and titratable acidity($1.057\~1.174\%$) were markedly changed f3r the storage at $20^{\circ}C$ for 20 days. Therefore the keeping quality of the drinkable yoghurts with addition of green tea powder was relatively good at $4^{\circ}C$ for 20 days. The results of sensory evaluation of the drinkable yoghurts containing peen tea powder indicated that flavor, sweet taste, mouthfeel and aftertaste of the drinkable yoghurt with $0.5\%$ green tea powder showed higher preference than others. And the drinkable yoghurt containing $0.5\% green tea powder added $20\%$(v/v) oligosaccharide had the higher sensory scores in sweet taste, aftertaste and overall acceptability among the treatments.