• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.6 no.3
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• pp.175-181
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• 1994

This paper deals with the correlation of absorption rate in absorber and evaporation rate in evaporator. The evaporator consists of a copper tube of 10mm dia, and 600mm long and chilled water flowing through the tube is fed by the chilled water circulator. The flowrate of LiBr-water solution in the absorber plays a significant role in determining the magnitude of the heat transfer rate from chilled water to refrigerant There exists a flowrate of solution which has a maximum value of heat transfer. It is interesting to note that the absorption rate of absorber increases with increasing the heat transfer rate of the evaporator. Also, absorption rate increases with evaportation rate, and the ratio(the former/the other) depends on the inlet temperature of LiBr-water solution in the absorber. The heating capacity in the absorber is higher than the refrigerating capacity in the evaporator.

• Clinical and Experimental Pediatrics
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• v.54 no.11
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• pp.429-435
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• 2011

Although Korean population has been growing steadily during the past four decades, the nation is rapidly becoming an aging society because of its declining birth rate combined with an increasing life expectancy. In addition, Korea has one of the lowest fertility rates in the world due to fewer married couples, advanced maternal age, and falling birth rate. The prevalence of low birth weight infants and multiple births has been increased compared with the decrease in the birth rate. Moreover, the number of congenital anomalies is expected to increase due to the advanced maternal age. In addition, the number of interracial children is expected to increase due to the rise in the number of international marriages. However, the maternal education level is high, single-mother birth rate is low, and the gender imbalance has lessened. The number of overweight babies has been decreased, as more pregnant women are receiving adequate prenatal care. Compared to the Asian average birth weight, the average birth weight is the highest in Asia. Moreover, the rate of low birth weight infants is low, and infant mortality is similarly low across Asia. Using birth data from Statistics Korea and studies of birth outcomes in Korea and abroad, this study aimed to assess the changes in maternal and infant characteristics associated with birth outcomes during the past four decades and identify necessary information infrastructures to study countermeasures the decrease in birth rate and increase in low birth weight infants in Korea.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.339-342
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• 1999

The equation of output voltage from the PVDF was derived. When impact force applied to the PVDF films of cantilever beam and one-end fixed, other-end supported beam structure, output voltage equation induced. Experimental output voltages by falling ball agreed quite well with induced theoretical data. This PVDF film showers to be in high possibility in a warning system of abnormal pulse rate and breathing, and in detecting impact force and/or mechanical energy.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.2125-2131
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• 1991

Evaporation rate constant, obtained by in this experimental study, of freely falling liquid fuel droplet on the condition of hot and pressurized environment are converted to critical evaporation constant according to Eq. of Ranz and Marshall. Critical evaporation constant, on constant environment pressuire, actively increase almost linearly with environment temperature increasing, but, on constant temperature, increases more or less with pressure increasing. Multycomponent droplet mixed with the fine fuel having a different of boiling point evaporate in order to boiling point, and each evaporation rate constant of mixed fuel equal to each fuel.

• Journal of Power System Engineering
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• v.15 no.3
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• pp.46-51
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• 2011

Low temperature vacuum drying technique, whose drying time and quantity of exhausting energy is about 25~30% of hot air drying, is very excellent in the drying efficiency. This paper is made out in the aspects of heat engineering with the object of developing Korean drying machine which can dry once a large quantity of objects to be dried in the state of low temperature and vacuum. As the results, it took about 17 hours(3~4 days in case of hot air drying) for material to reach about 18% of the final moisture content in order to store products for a long time, from about 78~80% of the early moisture content at the beginning of drying, and maximum drying rate comes to about 0.35 kg/m2hr at about 400% of the moisture content.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.202-206
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• 2009

Drying characteristics of fresh Korean-type rehmannia (jiwhang) noodle was investigated to determine drying kinetic parameters under the experimental conditions of 5 temperatures (30, 40, 60, 80, and $90^{\circ}C$). Drying curve of the noodle showed a biphasic pattern of decrease in drying rate with initial rapid drying followed by slow dehydration as the progress in drying. In all drying conditions, only falling drying rate period was observed and the drying rate of the noodle was greatly influenced by the drying temperature. The effective diffusion coefficients ($D_{eff}$) were determined by the diffusion model and their temperature dependency was determined using an Arrhenius equation. The activation energy ($E_a$) values for the drying of the noodle were 19.94 and 21.09 kJ/mol at the initial and the latter stage of dehydration, which were comparable to those of pasta or Japanese udong dehydration.

• International Journal of Advanced Culture Technology
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• v.3 no.2
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• pp.138-143
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• 2015

This paper was aimed to study the drying kinetics of coffee and to investigate the thin-layer drying kinetics of coffee by using a convective air dryer. The coffee was dried for the temperatures of 40, 50 and $60^{\circ}C$ with relative humidity in the range of 14-25% the airflow rate fixed at 1 m/s. According to the experiment result, the drying rate curve showed that drying process took place only in the falling rate period. Seven thin layer drying models (Newton, Page, Henderson and Pabis, Logarithmic, Wang and Singh, Two terms, Modified Henderson and Pabis) were fitted to the experimental moisture content data. The Two-trem model was found to be a better model for describing the characteristics of coffee for the temperatures of 40, 50 and $60^{\circ}C$. The effective moisture diffusivity of coffee increased when the drying temperature increased. The value was in the range of $4.5028{\times}10^{-11}$ to $6.4803{\times}10^{-11}m^2/s$.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.13 no.1
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• pp.60-67
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• 2006

Purpose: To identify the relationship between medication use and falls among hospitalized stroke patients. Method: The medical records of 472 patients with strokes were reviewed using a questionnaire on falling developed by the authors. Frequencies, percentages, means, standard deviations, and t-test and ${\chi}^2$-test, multiple logistic regression analysis were done using the SAS program. Results: The rate for falls by the patients during their stay in the hospital was 14.0%. The length of stay was longer and the morbidity duration of stroke shorter in the fall group than in the non-fall group. The use of sedatives, laxatives, and antidepressants was a significant predictor of falls and was associated with increase likelihood of falling(1.82, 1.81, 1.75 times respectively). Conclusion: In hospitalized stroke patients, there was a significant association between the use of sedatives, laxatives, antidepressants and falls. The number and kinds of ingested drugs was also associated with falls. It is necessary to further analyze the causes of falls based on results of the present study.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.10
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• pp.3293-3303
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• 1996

Numerical analyses have been performed to estimate the absorption heat and mass transfer coefficients in absorption process of the LiBr aqueous solution and the total heat and mass transfer rates in a vertical tube absorber which is coolING ed by air. Axisymmetric cylindrical coordinate system was adopted to model the circular tube and the transport equations were solved by the finite volume method. Absorption behaviors of heat and mass transfer were analyzed through falling film of the LiBr aqueous solution contacted by water vapor in tube. Effects of film Reynolds number on heat and mass transfer coefficients have been also investigated. Especially, effects of tube diameter have been considered to observe the total heat and mass transfer rates through falling film along the tube. Based on the analysis it has been found that the total mass transfer rate increases rapidly in a region with low film Reynolds number(10 ~ 40) as the film Reynolds number increases, while decreases beyond that region. The total heat and mass transfer rates increase with increasing the tube diameter.

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.5
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• pp.327-330
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• 2016

Currently, the world's elderly population continues to grow at a dramatic rate. As the number of senior citizens increases, detection of someone falling has attracted increasing attention for visual surveillance systems. This paper presents a novel fall-detection algorithm using motion estimation and an integrated spatiotemporal energy map of the object region. The proposed method first extracts a human region using a background subtraction method. Next, we applied an optical flow algorithm to estimate motion vectors, and an energy map is generated by accumulating the detected human region for a certain period of time. We can then detect a fall using k-nearest neighbor (kNN) classification with the previously estimated motion information and energy map. The experimental results show that the proposed algorithm can effectively detect someone falling in any direction, including at an angle parallel to the camera's optical axis.