• Journal of the Korean Society of Food Culture
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• v.5 no.2
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• pp.217-228
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• 1990

An ecological study of food and nutrition was conducted among 198 children, 6 to 12 years old, of the Songmyun elementary school and Samsong elementary school, located in remote villages of Chungchun-myun, Goisan-gun, Chung Buk Province between July 11 and 16, 1988. The results were summarized as follows. In regard to frequency of skipping breakfast, 3.3% of subjects skipped every morning; 15% often skipped; and the others never skipped. The most common reason for skipping a meal was lack of appetite. 6.6% of subjects often skipped an evening meal because of delayed meal preparation by a mother who returned home late. The survey found that 5.1% of subjects skipped a lunch at school. The reasons for skipping lunch were the mother’s being too busy to prepare a boxed lunch; a school bag too heavy to carry for a long distance to school; no adequate side-dishes for the boxed lunch. Growth patterns of those children having poor food habits, were reflected in lower figures in arm circumference and weight for height. The percentage of children having meals with their family on weekdays was 84.7% for breakfast; 85.6% for evening meal. About 7% of subjects had many dislikes and 74.1% had some dislikes in what they ate; 18.9% had good food preferences. There was a strong correlation between appetite or food preferences and anthropometric measurements or nutrient intake. Boiled rice was the predominant dietary staple, and principal sources of protein taken by subjects at home were soy beans and soy products. Regarding the boxed lunch prepared at home, most popular was one with only one kind of side-dish, including kimchee. 43.4% of the side-dishes were prepared with vegetables only. As for between meal snacks, milk and milk products, fruits and breads were popular among the subjects. The survey found that the children liked fruits, yogurt, corn, Chajang noodle; in contrast, lowest preference was for soup made with bones, curried meat with rice, and aromatic vegetables. The survey discovered a local dietary characteristics; 46.2% of the children customarily ate frog meat, an unconventional food.

• Journal of the Korean Electrochemical Society
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• v.3 no.2
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• pp.109-114
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• 2000

The relation between the phase-shift profile fur the intermediate frequencies and the Langmuir adsorption isotherm at the poly-Ir/0.1 M $H_2SO_4$ aqueous electrolyte interface has been studied using ac impedance measurements, i.e., the phase-shift methods. The simplified interfacial equivalent circuit consists of the serial connection of the electrolyte resistance $(R_s)$, the faradaic resistance $(R_F)$, and the equivalent circuit element $(C_P)$ of the adsorption pseudoca-pacitance $(C_\phi)$. The comparison of the change rates of the $\Delta(-\phi)/{\Delta}E\;and\;\Delta{\theta}/{\Delta}E$ are represented. The delayed phase shift $(\phi)$ depends on both the cathode potential (E) and frequency (f), and is given by $\phi=tan^{-1}[1/2{\pi}f(R_s+R_F)C_P]$. The phase-shift profile $(-\phi\;vs.\;E)$ for the intermediate frequency (ca. 1 Hz) can be used as an experimental method to determine the Langmuir adsorption isotherm $(\theta\;vs.\;E)$. The equilibrium constant (K) for H adsorption and the standard free energy $({\Delta}G_{ads})$ of H adsorption at the poly-Ir/0.1 M $H_2SO_4$ electrolyte interface are $2.0\times10^{-4}$ and 21.1kJ/mol, respectively. The H adsorption is attributed to the over-potentially deposited hydrogen (OPD H).

• Journal of the Korean Electrochemical Society
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• v.3 no.1
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• pp.25-30
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• 2000

The relation between the phase-shift profile for the intermediate frequencies and the Langmuir adsorption isotherm at the poly-$Pt/0.1\;M\;H_2SO_4$ aqueous electrolyte interface has been studied using ac impedance measurements, i.e., the phase-shift methods. The suggested interfacial equivalent circuit consists of the serial connection of the electrolyte resistance ($R_S$), the faradaic resistance $(R_F)$ and the equivalent circuit element $(C_P)$ of the adsorption pseudocapacitance $(C_\varphi)$. The delayed phase shift $(\varphi)$ depends on both the cathode potential (E) and frequency (f), and is given by $\varphi=-tan^{-1}[1/2{\pi}f(R_s+R_F)C_p]$. The phase-shift profile $(\varphi\;vs.\;E)$ for the intermediate frequency (ca. 6Hz) can be used as an experimental method to determine the Langmuir adsorption isotherm (9 vs. E). The equilibrium constant (K) for H adsorption and the standard free energy $({\Delta}G_{ads})$ of H adsorption at the poly-$Pt/0.1\;M\;H_2SO_4$ electrolyte interface are $1.8\times10^{-4}\;and\;21.4kJ/mol$, respectively. The H adsorption is attributed to the over-potentially deposited hydrogen (OPD H).

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.12
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• pp.1-8
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• 2006

An experimental study was carried out in order to investigate the influence of Reynolds number on the near-wake of an oscillating airfoil. An NACA 0012 airfoil was sinusoidally pitched at the quarter chord point, and is oscillated over a range of instantaneous angles of attack of $\pm$6$^{\circ}$. An X-type hot-wire probe was employed to measure the near-wake of an oscillating airfoil, and the smoke-wire visualization technique was used to examine the flow properties of the boundary layer. The free-stream velocities were 1.98, 2.83 and 4.03 m/s and the corresponding chord Reynolds numbers were 2.3${\times}10^4$, 3.3$\times$104 and 4.8${\times}10^4$, respectively. The frequency of airfoil oscillation was adjusted to fix a reduced frequency of K=0.1. The results show that the properties of the boundary layer and the near-wake can dramatically be distinguished in the range of Reynolds numbers between 2.3${\times}10^4$ and 3.3${\times}10^4$, on the other hand, it is similar in the cases of Re=3.3$\times$104 and 4.8$\times$104. This is caused by that the unsteady separation point is dramatically delayed in case of Re= 2.3${\times}10^4$.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.1
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• pp.11-18
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• 2012

Daily temperature data produced by harmonic analysis of monthly climate summary have been used as an input to plant phenology model. This study was carried out to evaluate the performance of the harmonic based daily temperature data in prediction of major phenological developments and to apply the results in improving decision support for agricultural production in relation to the climate change scenarios. Daily maximum and minimum temperature data for a climatological normal year (Jan. 1 to Dec. 31, 1971-2000) were produced by harmonic analysis of the monthly climate means for Seoul weather station. The data were used as inputs to a thermal time - based phenology model to predict dormancy, budburst, and flowering of Japanese cherry in Seoul. Daily temperature measurements at Seoul station from 1971 to 2000 were used to run the same model and the results were compared with the harmonic data case. Leaving no information on annual variation aside, the harmonic based simulation showed 25 days earlier release from endodormancy, 57 days longer period for maximum cold tolerance, delayed budburst and flowering by 14 and 13 days, respectively, compared with the simulation based on the observed data. As an alternative to the harmonic data, 30 years daily temperature data were generated by a stochastic process (SIMMETEO + WGEN) using climatic summary of Seoul station for 1971-2000. When these data were used to simulate major phenology of Japanese cherry for 30 years, deviations from the results using observed data were much less than the harmonic data case: 6 days earlier dormancy release, 10 days reduction in maximum cold tolerance period, only 3 and 2 days delay in budburst and flowering, respectively. Inter-annual variation in phenological developments was also in accordance with the observed data. If stochastically generated temperature data could be used in agroclimatic mapping and zoning, more reliable and practical aids will be available to climate change adaptation policy or decision makers.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.5
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• pp.324-333
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• 2013

Recently, rudder erosion due to cavitation has been frequently reported on a semi-spade rudder of a high-speed large ship. This problem raises economic and safety issues when operating ships. The semi-spade rudders have a gap between the horn/pintle and the movable wing part. Due to this gap, a discontinuous surface, cavitation phenomenon arises and results in unresolved problems such as rudder erosion. In this study, we made a rudder model for 2-D experiments using the NACA0020 and also manufactured gap flow blocking devices to insert to the gap of the model. In order to study the gap flow characteristics at various rudder deflection angles($5^{\circ}$, $10^{\circ}$, $35^{\circ}$) and the effect of the gap flow blocking devices, we carried out the velocity measurements using PIV(Particle Image Velocimetry) techniques and cavitation observation using high speed camera in Seoul National University cavitation tunnel. To observe the gap cavitation on a semi-spade rudder, we slowly lowered the inside pressure of the cavitation tunnel until cavitation occurred near the gap and then captured it using high-speed camera with the frame rate of 4300 fps(frame per second). During this procedure, cavitation numbers and the generated location were recorded, and these experimental data were compared with CFD results calculated by commercial code, Fluent. When we use gap flow blocking device to block the gap, it showed a different flow character compared with previous observation without the device. With the device blocking the gap, the flow velocity increases on the suction side, while it decreases on the pressure side. Therefore, we can conclude that the gap flow blocking device results in a high lift-force effect. And we can also observe that the cavitation inception is delayed.

• Food Science of Animal Resources
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• v.42 no.5
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• pp.816-832
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• 2022

To evaluate the effects of early postmortem vacuum packaging (VP) on meat quality during postmortem chilled storage, hot-boned lamb was vacuum-packaged at 1, 6, 12, 24, and 48 h postmortem and stored around 2℃ until 168 h postmortem, with lamb packaged in plastic wrap as the control (aerobic packaging). Intramuscular pH decline was delayed when lamb was vacuum packaged at 1, 6, and 12 h postmortem (p<0.05). The lamb vacuum-packaged at 1 h postmortem (VP-1h group) had significantly lower shear force values and purge losses accompanied by lower free thiol group values than other treatments during postmortem storage and was also higher in extractable calpain-1 activity by 6 h postmortem (p<0.05). Free thiol group concentrations were significantly higher after VP at 6 and 12 h postmortem (p<0.05). Packaging lamb under vacuum very early postmortem produced the lowest shear force and purge loss, likely by slowing heat loss and muscle temperature decline, implying that lamb quality is improved by VP when applied very early postmortem. This was at the expense of protein oxidation, which was unrelated to other meat quality measurements, most likely because potential contracture during hot boning confounded its impact. Further research is required to understand the implications of the interaction between protein oxidation, VP, and hot boning on the acceptability of lamb.

• Journal of Acupuncture Research
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• v.17 no.1
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• pp.27-41
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• 2000

The meridian system is the most essential and basic connecting structure that maintains the vital activities of viscera and bowels by connecting them with each part of body's surface. Doctors can understand the healthy condition, and the region and deficiency-excessiveness of disease by observing the condition of Qi flowing. Deficiency and excessiveness could be differentiated by various symptoms expressed in meridian system. Especially there could be several clues like pain, heat-cold, protuberance-depression, change of color and shine in the line of channel leads to the judgment of deficiency-excessiveness The diagnosis of deficiency and excessiveness can be generalized by quantification of elastic status in skin surface along the meridian system. By comparing data from measurement of elastic condition with those from traditional deficiency and excessiveness, it could be utilized for the development of oriental medicine. All biological activities in the human body are based on meridian system according to the oriental medicine. Also the meridian system is viewed as basic and essential structure connecting internal viscera and each part of body. The areas of expressed channel phenomena are muscle to bone, muscle to muscle and bone to bone. These areas are called depression where meridian system is present and any changing state on those points can be measured. It could be difficult in diagnosing the reaction of meridian system because doctor can depend on his own judgment. Therefore, it is necessary to quantify and indexate channel reactions. To quantify the channel reactions, specially manufactured instrument was used to quantify the protuberance and depression to differentiate the deficiency and excessiveness. The results follow as below; 1. The elastic index measurement by the equipment proved a pattern of agreement showing the values that ranged within standard deviation 0.05kgf/cm throughout the experiment except few cases' measurement in CV-17. 2. To evaluate the state of deficiency & excessiveness of elastic index measurements in frontal point, elastic index measurements in the front paint were compared to the elastic index measured surrounding the point within 2.5 cm. Such result of indexing procedure was closely matched to the concept of palpitation. 3. If the elastic index values in the surrounding front point closely located to the elastic index values in the front point, the judgement on the state of deficiency and excessiveness was delayed. Otherwise, it was judged as deficiency or excessiveness. 4. Out of total 12 cases of comparing the elastic index values to the elastic index values in the surrounding front point, Three to nine front points were judged as either in the state of deficiency or excessiveness. 5. Among the nine front points judged as either in the state of deficiency or excessiveness, Four cases were matched to the electric index measured by EAV that evaluating the internal organs by five different phases. If more clinical cases are accumulated, it is expected to systematically theorize and improve the concept of deficiency and excessiveness in the internal organs using the front point.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.813-822
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• 1998

Background: Extubation is recommended to be performed at minimum pressure support (PSmin) during the pressure support ventilation (PSV). In field, physicians sometimes perform additional 1 hr T-piece trial to the patient at PSmin to reduce re-intubation risk. Although it provides confirmation of patient's breathing reserve, weaning could be delayed due to increased airway resistance by endotracheal tube. Methods: To investigate the effect of additional 1 hr T-piece trial on weaning outcome, a prospective study was done in consecutive 44 patients who had received mechanical ventilation more than 3 days. Respiratory mechanics, hemodymic, and gas exchange measurements were done and the level of PSmin was calculated using the equation (PSmin=peak inspiratory flow rate $\times$ total ventilatory system resistance) at the 15cm $H_2O$ of pressure support. At PSmin, the patients were randomized into intervention (additional 1 hr T-piece trial) and control (extubation at PSmin). The measurements were repeated at PSmm, during weaning process (in cases of intervention), and after extubation. The weaning success was defined as spontaneous breathing more than 48hr after extubation. In intervention group, failure to continue weaning process was also considered as weaning failure. Results: Thirty-six patients with 42 times weaning trial were satisfied to the protocol. Mean PSmin level was 7.6 (${\pm}1.9$)cm $H_2O$. There were no differences in total ventilation times (TVT), APACHE III score, nutritional indices, and respiratory mechanics at PSmin between 2 groups. The weaning success rate and re-intubation rate were not different between intervention group (55% and 18% in each) and control group (70% and 20% in each) at first weaning trial. Work of breathing, pressure time product, and tidal volume were aggravated during 1 hr T-piece trial compared to those of PSmin in intervention group ($10.4{\pm}1.25$ and $1.66{\pm}1.08$ J/L in work of breathing) ($191{\pm}232$ and $287{\pm}217$cm $H_2O$ s/m in pressure time product) ($0.33{\pm}0.09$ and $0.29{\pm}0.09$ L in tidal volume) (P<0.05 in each). As in whole, TVT, and tidal volume at PSmin were significantly different between the patients with weaning success ($246{\pm}195$ hr, $0.43{\pm}0.11$ L) and the those with weaning failure ($407{\pm}248$ hr, $0.35{\pm}0.10$L) (P<0.05 in each). Conclusion : There were no advantage to weaning outcome by addition of 1 hr T-piece trial compared to prompt extubation to the patient at PS min.

• The Korean Journal of Nuclear Medicine
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• v.12 no.1
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• pp.17-28
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• 1978

A simplified photoelectric apparatus producing graphic records of the free Achilles tendon reflex allowed us to study the reflex quantitatively in subjects with normal and abnormal thyroid function. In this study Achilles tendon reflex times were tested in 340 normal Korean persons, 89 hyperthyroid patients, 19 hypothyroid patients and 85 other thyroid disease patients who were euthyroid in thyroid function tests. In normal Korean persons, the Achilles tendon reflex time was delayed with increasing age and slower in female than in male. They showed good correlationship with various thyroid function tests which included ETR, $T_3RU,\;^{131}I$ thyroid uptake and serum TSH. Diagnostic accuracy of them was 71% in hyperthyroidism and 90% in hypothyroidism. Finally the serial measurements of them were very useful tests in evaluating the clinical coures of hyperthyroidism and hypothyroidism once treatment was begun.