• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.2
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• pp.18-24
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• 1999

Liquid ramjet combustor is closely connected with complex phenomena due to a series of processes such as intake air, spray, mixing, and combustion. The present numerical experiments were peformed to investigate these flow characteristics for two and three dimensional liquid ramjet combustor. Grid system was made with three domains: intake region where air is supplied and fuel is injected, combustor and nozzle region, and exit atmosphere region. The numerical results showed that two and three dimensional flow patterns in recirculation region of combustor were significantly different each other and spray model was necessary to predict correctly the chemical reaction flow characteristics. Numerically examined for two different location of fuel injector, one is located on the bottom position of curved intake and the other is located on the top position. We found that bottom position of fuel injector is better than top position because fuel influx to the recirculation region which is need to sustain chemical reaction is more than the latter.

• Transactions of Materials Processing
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• v.25 no.5
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• pp.325-331
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• 2016

In this paper, a three-dimensional part model is constructed for the finite element analysis of hemming models where hemming defects frequently occur. The roller path is modeled as the boundary condition with the one-dimensional beam element and the revolute joint model. With the constructed part model and the roller movement, a finite element analysis has been pursued in order to identify the hemming load and hemming defects such as wrinkling in the flange region. The analysis result shows that the maximum hemming load occurs in the intake situation while oscillatory behavior of the load is found especially when hemming the curved model because of wrinkle generation. This paper compares the amplitude and the period of wrinkle between the analysis result and the experiment, which shows good agreement with each other.

• Journal of Ship and Ocean Technology
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• v.12 no.3
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• pp.36-54
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• 2008

A jet stream applied tangential to a curved surface in fluid increases lift force by strengthening circulation around the surface and this phenomenon is known as the Coanda effect. Many experimental and numerical studies have been performed on the Coanda effect and the results found to be useful in various fields of aerodynamics. Recently, preliminary studies on Coanda control surface are in progress to look for practical application in marine hydrodynamics since various control surfaces are used to control behaviors of ships and offshore structures. In the present study, the performance of a Coanda control surface with different geometries of the jet injection nozzle was surveyed to assess applicability to ship rudders. A numerical simulation was carried out to study flow characteristics around a section of a horn type rudder subjected to a tangential jet stream. The RANS equations, discretized by a cell-centered finite volume method were used for this computation after verification by comparing to the experimental data available. Special attentions have been given to the sensitivity of the lift performance of a Coanda rudder to the location of the slit (outlet) and intake of the gap between the horn and rudder surface at the various angles of attack. It is found that the location of the water intake is important in enhancing the lift because the gap functions as a conduit of nozzle generating a jet sheet on the rudder surface.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.6
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• pp.569-578
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• 2008

The Coanda effects demonstrate that a jet stream applied tangential to a curved surface can generate lift force by increasing the circulation. Many experimental and numerical studies have been performed on the Coanda effect and it is found to be useful in various fields of aerodynamics. The Coanda effect may have practical application to marine hydrodynamics since various control surfaces are being used to control behaviors of ships and offshore structures. In the present study, numerical computations are performed to find the applicability of the Coanda effect to the marine control surfaces. For the purpose, changes in flow characteristics around a flapped foil due to the Coanda effect have been simulated by RANS equations discretized with a cell-centered finite volume method (FVM). In the process, special attention has been given to the influence of jet nozzle arrangement on the lift characteristics of the Coanda foil. It is found that the shape as well as the location of the jet intake and jet exit affects the lift performance of the foil significantly.

• Research in Community and Public Health Nursing
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• v.9 no.1
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• pp.40-63
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• 1998

A long life is the desire of many people. The purpose of this study was to describe long life factors for people aged one hundred and above on Chju island. The research was conducted using a phenomenological method to add understanding to this subject. The field work for this study was done from July, 1997 to February, 1998 on Cheju island. The sample consisted of 10 persons of one hundred or above and 12 families. They were audio-recorded and analyzed using Colaizzi's (1978) method. The results of the present study shows the following: The thoughts of the persons one hundred and above showed ten important concepts; 'dietary regimen', 'mental regimen', 'sleep regimen', 'residence regimen', 'health regimen', 'labor regimen', 'exercise regimen', 'being born', 'filial piety and posterity', 'attachment to life'. Concerning 'Dietary Regimen': Dietary regulation, Preferential food intake, Living on vegetables, Light eating, and concern for longevity in food intake were important. Concerning 'Mental Regimen' : Harmony, Clearheadedness, Mildness, Abstinence, Generosity, Relaxation, Gaiety, Inspiration and Strength were important. Concerning 'Sleep Regimen'; Enough sleeping hours, Sound sleep, Curved sleeping posture, and Comfortable bedding were important. Concerning 'Residence Regimen' ; Clean dwelling, Pleasant surroundings, Thatched house life, Living in the village with good-hearted people, and Regular life were important. Concerning 'Health Regimen'; Temperance of drug, use Proper temperature, Proper humidity, and a Clean body were important. Concerning 'Labor Regimen'; Agricultural labor, Diligence, and Domestic labor were important. Concerning Exercise Regimen': Proper exercise, and Sunbathing were important. Concerning 'Being Born' ; Strong physical constitution, Longevity lineage, and Destiny were important. Concerning 'Filial Piety and Posterity' : Showing respect to a long-lived elder and Reducing anxiety were important. Concerning 'Attachment to Life' ; The desire to live long was important. The following conclusion was made from the above results. Human beings cannot avoid death, but the span of life can be prolonged to the maximum span of human life by wisdom, health care, and proper environmental conditions. As a result, a health regimen must be imposed for longevity such as controling food intake, having positive thoughts, being relaxed, sleeping enough, clean dwelling, taking care of oneself which can improve immunity and resistance to decrease, as well as proper labor and exercise. In addition, when filial piety is served, the desire of longevity and retaining one's youthfulness for a long time can be achieved. These should be done to live long and lead a qualitative life. By the results of this research, the following is suggesed for nursing. To satisfy the basic nursing principle that nursing must be practiced to help people live long, education must be spread to people who are nursed and their family so that they can lead a healthy life. And in nursing elders, nurses must recognize that elders have a strong desire for life, even though they may have negative thoughts about life at times. Therefore nurses have to respect the elders' value of life, and help them improve their self-esteem and self -fulfilment.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.470-473
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• 2000

The experiment was carried out to evaluate the effect of varying levels of flaked com abomasally infused on energy metabolism and nitrogen metabolism in fattening steers. The starch levels of flaked corn of abomasally infused were 0, 300, 600 and 900 g/d. Four mature fattening steers fitted with permanent abomasum cannulas were allocated to a $4{\times}4$ Latin square design were fed at 1.2 maintenance requirement a basal diet of Chinese wildrye (Aneurolepidium Chinense). Compared with 0 g/d (control group), digestible nitrogen, retention nitrogen (RN, g/d) and the efficiency of digestible nitrogen converted into retention nitrogen (RN/DN, %) of 300, 600 and 900 g/d groups were higher (p<0.05). The post-ruminal starch digestion of flaked corn were 71.36, 80.27 and 64.71 % when the amounts abomasally infused were 300, 600 and 900 g/d, respectively. When the amount of starch abomasally infused was more than 600 g/d, the post-ruminal digestion of starch decreased. 300, 600 and 900 g/d starch infusion groups showed higher metabolizable energy intake (ME) and net energy gains (NEg, MJ/d) than the control group, and the efficiencies of metabolizable energy converted into body weight (Kf, %) of these groups were higher than the control group by 38.31, 73.18 and 67.06% (p<0.05). Kf (Y, %) had a positive curved relation to starch of flaked com abomasally infused (X, g/d), $Y=36.1605X^{0.0760}$ (n=16, r=0.9308).