• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.5
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• pp.422-430
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• 2001

In the present study, an evaporative generation process of ammonia-water solution film on the vertical plate was analysed. For the utilization of waste heat, hot water of low temperature was used as the heat source. The continuity, momentum, energy and diffusion equations for the solution film and vapor mixture were formulated in integral forms and solved numerically. Counter-current solution-vapor flow resulted in the refrigerant vapor of the higher ammonia concentration than that of co-current flow. Eve the rectification of refrigerant vapor was observed near the inlet of solution film in counter-current flow. For the optimum operation of generator using hot water, numerical experiments, based on the heat exchange and generation efficiencies. revealed the inter-relationships among the Reynolds number of the solution film and hot water, and the length of generator. Enhancement of heat and mass transport in the solution film was found to be very effective for the improvement of generation performance, especially at high solution flow rate.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.17 no.5
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• pp.583-589
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• 1988

Condensation of water vapor into an absorbent liquid of LiBr-water solution falling over a bank of water cooled horizontal tubes was investigated theoretically. The governing conservation equation for a re-defined physical transport phenomena were solved numerically using a finite difference method. Raw parameters were used in this study, since reliable experimental data is required prior to a dimensionless parametric study. The average values of wall heat transfer coefficient and interfacial absorption rate were defined to see the system performance. Other parameters include tube diameter, streamwise coordinate (and number of tubes in row), mass flow rate, and the wall temperature. The effects of these quantities on the absorption processes and suggestions for a rational system design have been presented.

• Journal of the Korean Society of Safety
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• v.11 no.1
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• pp.108-120
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• 1996

It is a problems in industrial accidents that the knowledge for industrial accidents is obtained by experience, not by experiment. This experiential knowledge is obtained by Investigating accident cases and utilizing those for safety education. Therefore, in this paper, the situation about the serious accident of construction is analyzed by occupation, a kind of construction, time group, season, type of accident, and accidental cause. And the mutual · relations of these factors are studied. The most frequent type of the serious accidents of construction Is the falling accident. It happenes most frequently at apartment construction among kinds of construction and to structural worker, finishing worker, normal worker in order among occupations. And it is found that the most critical causes of the falling accident are the imperfection of safety facilities and unwearing of protection equipments, so a number of accidents can be reduced by the expansion of safety facilities and wearing of protection equipments absolutely. The counterplan of prohibition of accidents and the direction of government policy are presented by a series of nalyses for accident cases.

• The Journal of Korea Robotics Society
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• v.13 no.4
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• pp.248-255
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• 2018

In this paper, a design for a vehicle body of an armored robot for complex disasters is described. The proposed design considers various requirements in complex disaster situations. Fire, explosion, and poisonous gas may occur simultaneously under those sites. Therefore, the armored robot needs a vehicle body that can protect people from falling objects, high temperature, and poisonous gas. In addition, it should provide intuitive control devices and realistic surrounding views to help the operator respond to emergent situations. To fulfill these requirements of the vehicle body, firstly, the frame was designed to withstand the impact of falling objects. Secondly, the positive pressure device and the cooling device were applied. Thirdly, a panoramic view was implemented that enables real-time observation of surroundings through a number of image sensors. Finally, the cockpit in the vehicle body was designed focused on the manipulability of the armored robot in disaster sites.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.229-238
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• 2007

This paper presents a study on construction safety in the People Democratic Republic of Laos (PDRL). Fifty workers experienced certain injuries in their construction sites and 15 top managers were interviewed in twenty-six construction projects in Vientiane, the capital of PDRL. Research results show that stepping on and/or striking against objects (48%), struck by falling objects (24%), falling of persons (12%) are major types of construction injuries. The paper stresses that the ignorance of top managers about their crucial role in safety improvement, using safety incentive to raise safety performance, lack of thorough understanding about benefit from labor safety performance, and the willingness to cut off safety performance expenditures is considered as obstructions of safety improvement programs. The survey indicates that physical working conditions, relationship among workers, foremen behaviors and the monthly wage were influencing factors to worker's job satisfaction. The study also highlights afternoon as dominant time that led to a large number of injuries.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.342-349
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• 1982

Filefish muscle in the form of thin plate $(5{\times}10{\times}0.4\;cm)$ was dried in a forced air dryer at $47.5^{\circ}C$ to study the relation between dehydration mechanism and water activity. The dryer was designed in such a way that the temperature, relative humidity and velocity of air could be controlled. The whole dehydration process of the filefish muscle was divided into two different drying rate periods, constant and falling rate period. During the constant drying rate period, the drying rate was proportional to the square root of air velocity under the conditions of constant temperature and relative humidity of air. The falling rate period was further divided into two different falling drying rate periods, first and second falling rate period. The first falling rate period was an unsaturated surface drying period caused by partial unsaturation of the drying surface with capillary condensed free water diffused from the internal part of the filefish muscle. At this stage he drying rate was mainly dependent on the relative humidity at constant air temperature, and case-hardening phenomenon started at the end of this stage. The moisture content and the water activity at which the second falling rate period started were not constant, because the drying rate of the first falling rate period was strongly dependent on the air humidity. The second falling rate period was again divided into two drying rate periods, former and latter period. The drying rates of both of these periods were independent on the external air humidity. During the former period of the second falling rate period, the dehydration was proceeded by diffusion and vaporization of capillary condensed free water in filefish muscle. The diffusion coefficient of water was $2.89{\times}10^{-10}m^2/sec\;at\;47.5^{\circ}C$. At this stage, the case-herdening continued until the water activity reduced to 0.7. The latter period of the second falling rate period started at the water activity of 0.45. The dedydration was proceeded by diffusion and vaporization of bound water, which adsorbed in multimolecular layers, through the hardened drying surface. The number of molecular layers was 4, and the diffusion coefficient of water during this stage was $4.38{\times}10^{-11}m^2/sec\;at\;47.5^{\circ}C$.

• Food Science and Preservation
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• v.19 no.3
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• pp.361-367
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• 2012

The purpose of this study was to investigate the rheological properties of pound cake cotaining ginger powder. Ginger powder was added to pound cake bases at 1, 3 and 5%. concentrations. The physical properties of the pound cake with ginger powder were tested by rapid viscoanalyzer (RVA), a farinogram, and an alveogram. The falling numbers were increased with the increment of ratio of ginger powder, but they did not show a significant difference. The higher quantity of ginger powder with cake flour made MTI value the higher and these results showed typical cake flour. The farinogram quality number did not show a significant difference between the control and the other samples. The highest initial gelatinization temperature was that of the control, and the increment of ginger powder on the cake flour made initial gelatinization temperature lower. The peak and final viscosities, however, were higher with the quantity increment of ginger powder. The holding strength did not show a significant difference. As the 5% - ginger-powder pound cake showed the highest setback, it was predicted that the addition of ginger powder to the flour would not play the role of anti-retrogradation. The Pmax and L value of the alveogram decreased with the ginger powder increments.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.3
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• pp.175-183
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• 2021

Purpose : Few studies have examined the relationship between elderly falls and quality of life (QOL) in a large general population. Furthermore, although many studies have investigated the relationships between socio-demographic factors and falls, relatively few studies have evaluated the associations of places and environments with QOL of fall. The purpose of the scheme was to identify the relationship between falls and QOL in a large sample of the elderly. Methods : This study used raw data from the 2013 Korean community health survey. A total of 228,781 people participated in the 2013 study among them 61.552 people were aged 65 or older. Authors also excluded 40 people whose QOL confirmation was unclear. Therefore, final analysis was conducted 61,512 senior citizens. The survey contained questions about the occurrence of falls, number of falls occurring per year, location of occurrence, and cause of falls. QOL was measured using the EQ-5D, an evaluation tool developed by the EuroQol group. Results : The results showed a statistically significantly lower QOL to little fear and full of fear as compared with no fear of falls (p<.05). The number of falls was statistically significantly lower in one, two, and three or more times, than in zero (i.e. no falls)(p<.05). In the falling environments, fall experience, but not related to lighting (p>.05), had a significant lower in QOL compared without the experience (p<.05). Conclusion : This study concluded that there is a strong connection between fall and QOL to the elderly, particularly regarding the number of occurrences, place, and environment. However, we found that an environment (e.g. the lack of lighting) might not affect QOL. It means that when the experts who make an effective tool or intervention may not need to consider indoor and outdoor darkness.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1324-1330
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• 2007

In this paper, we propose pattern recognition algorithm for activities of daily living by adopting extreme learning machine based on single layer feedforward networks(SLFNs) to the signal from bidirectional accelerometer. For activity classification, 20 persons are participated and we acquire 6, types of signals at standing, walking, running, sitting, lying, and falling. Then, we design input vector using reduced model for ELM input. In ELM classification results, we can find accuracy change by increasing the number of hidden neurons. As a result, we find the accuracy is increased by increasing the number of hidden neuron. ELM is able to classify more than 80 % accuracy for experimental data set when the number of hidden is more than 20.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.12
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• pp.1214-1222
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• 2001

The present study investigated the effect of diameter and length on the absorption performance of a vertical falling film type absorber using $LiBr-H_2$O solution of 60 wt%. The parameters were diameter of absorber (17.2, 23.4, 31.1 mm), length of absorber (771, 1150, 1528 mm), and film Reynolds numbers (50, 70, 90, 110, 130, 150). As the diameter of the absorber was increased, the absorption mass flux, Sherwood number, heat flux, and heat transfer coefficient were increased, in which Sherwood number and heat transfer coefficient were increased up to 13% and 30% respectively. As the length of the absorber was increased, the total absorption rate and heat transfer coefficient were increased by 37% and 35% respectively, while the absorption mass flux was decreased.