• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.73-75
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• 2011

In this study, prediction of later-age compressive strength of ultra-high strength concrete, based on the accelerated strength of concrete cured in 50, 60℃ warm water was investigated. W/B of 32, 23.5, 19% 3 levels were examined. And the specimens were cured in 50, 60℃ warm water. The results showed reliable accuracy by regression relation between 28day strength cured by standard curing method and accelerated strength of the concrete cured in warm water. And the specimens cured in 50, 60℃ showed more high strength development. So 60℃ curing could be considered in order to reduce the measurement error. As a result, the feasibility of 50, 60℃ warm water curing method at high strength level was confirmed.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.244-247
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• 2001

Lubricanting characteristics in the warm forging have influence on forgeability of products. but Research on deformation characteristic of warm forging on the lubricant and lubricating method lack. This paper deform a bevel gear by warm forging and evaluate deformation loads and quality of products by each lubricants and lubricating method using oil-based lubricants(Soy, Oildag) and water-based lubricants(Deltaforge $\#31$, Renite S-26-X, Deltaglaze $\#151$). In conclusion, the less a deformation load by lubricants the more improvement a quality of product in manufacture of a bevel gear and water-based lubricants in the warm forging reduce a deformation load and improve a quality of products. Especially, Deltaforge $\31$ have excellent characteristic in the warm forging.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.93-94
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• 2012

In this study, prediction of later-age compressive strength of ultra-high strength concrete, based on the accelerated strength of concrete cured in 80℃ warm water was investigated. As a result, the nature of ultra-high strength concrete showed a rapid early strength enhancement, compressive strength using warm water method of 80℃ at 2days is same compressive at 28days using standard curing.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.119-123
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• 1995

This paper presents an accelerated-curing method by the war water method and discusses how these methods can be adapted for regular quality control and quality assurance of concret. Accelerated strength test data can be used for estimating the furture stength, e.g. the 28-day strength. An accelerated-curing method to predict the 28-day strength of concrete from 1-day warm water-cured test results was evaluated in the laboratory and the field. For these evaluations test are performed for 1845 standard specimens from 123 different batches of concrete. The results of this study the equation applicable universally with resonable accuracy are presented for estimating the potential strength of concrete by the warm water-curing method.

• 한국기계가공학회지
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• 제17권2호
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• pp.22-29
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• 2018

The purpose of this study was to evaluate the performance of a solar collector to introduce natural convection in a water tank as a means of obtaining warm water. Numerical analysis was performed to predict the characteristics of the solar collector and its performance was verified using an experimental method. The single vacuum structure of the collector enabled natural convection when it was fitted on the water tank. Based on numerical analysis, warm water of $31-54^{\circ}C$ was obtained when the inlet temperature of cold water was $20^{\circ}C$. Furthermore, the temperature of the warm water could be predicted under various conditions as well as the experimental conditions created for this study.

• 수산경영론집
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• 제37권1호
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• pp.73-93
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• 2006

This paper tries to apply the standard method for the estimation of range and degree of fisheries damages caused by warm water drained by generating plants to a real situation. The theoretic foundation of the study has been shown in the article published on the journal of fisheries business administration of last year. The paper tries to examine the degree of external appicability of the theoretic model through empirical study. The results of the study are as follows. The model has been found a successful device for the estimation of fisheries damages caused by warm water drained by generating plants. It also shows a possibility to work in any other fisheries damage cases caused by several kinds of public undertaking on coastal areas. The key of the model is the successful derivation of the quantity amount of the critical variation of environmental factors for example, in this case, water thermal variation. Therefore the countinous and appropriate collection of law data on the environmental factors under a viewpoint of statistics is essential to the usefulness of the model.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.200.2-200.2
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• 2010

This study was carried out in order to reduce the amount of underground water which is used in the water curtain system for retaining heat. To proceed to the research, two plastic green houses of water curtain system were installed. One was equipped of internal small tunnel for keeping warm air in the interior of the house. Then the internal small tunnel for keeping warm air was fitted with PVC duct of 50cm in diameter filled with subsurface water. Storing surplus solar energy in the water filled in PVC duct was the method used to this house. Another was installed with FCU in the middle of the house, and was fitted a circulation motor in water tank for heat storage which was operated from 10 a.m. to 4 p.m. in order to interchange heat with FCU. The latter was installed with four FCUs which has a capacity of 8000kcal per hour. Consequently about 5 degrees celsius could be maintained in the interior of the internal small tunnel for keeping warm air with the external temperature of more than minus 5 degrees celsius. It appeared that the alteration of an internal temperature of the house was flexible depending on the sunlight during daytime. It happened that to prevent the water from freezing, mixing antifreezing liquid in the flowing water of FCU or changing the operating method of FCU was a suitable measure. Also, in order to use the surplus solar thermal energy on plastic green house of water curtain system efficiently, storing the surplus heat during daytime simultaneously finding a method of using water curtain systematic underground water happened to be important. As a result of this research, when the house's interior temperature is below zero the operation of FCU appeared to be impossible. Therefore when supposed that the amount of water used in the house is 150~200ton for stable operation of FCU, using the system mentioned in the above research happened to be appropriate of reducing the amount of subsurface water from 80% to 100% when maintaining the interior of internal small tunnel's temperature for keeping warm air of 5 degrees celsius at the extreme temperature of minus 5 degrees celsius.

• 한국정밀공학회지
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• 제22권3호
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• pp.21-28
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• 2005

In the hot forging process lubricant influences on frictional condition only, but in the warm forging process it influence on the formability such as dimensional accuracy, filling state and frictional condition and it is important to estimate a lubricating characteristic of lubricants in the warm forging. In this paper, in order to evaluate the formability of billet in warm forging process according to the lubricant and lubricating method, lubricant and lubricating test have been performed using oil-based and water-based lubricant which were widely used in the hot and warm forging processes. The surface roughness of initial billet was measured to evaluate the influence on the formability of billet and the forming load and dimensional accuracy were compared and evaluated. From the experimental results, it can be known that water-based lubricants are more excellent than oil-based lubricants for warm forging of complex shape like a bevel gear. Also, in this study characteristics of deformation have been investigated according to surface treatment of initial billet.

• 한국세라믹학회지
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• 제35권4호
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• pp.371-377
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• 1998

HAC/PVA계 MDF 시멘트 복합재료의 수분안정성을 향상시키기 위하여 수용성 epoxy resm을 시멘트 중량에 대해 5wt% 에서 15wt%까지 첨가하고 calendering법, extruding법, warm pressing법으로 성형하여 epoxy resin첨가량 및 제조공정이 수분안정성에 미치는 영향을 살펴보았다. 제조된 시편은 건조상태 및 3일, 7일, 14일간 물 속에 침적 후 습윤강도를 3점 곡강도로 측정하고 SEM으로 표면 가까운 부분의 파단면을 관찰하고 수은압입법으로 기공분포 및 기공율을 분석하여 침수 재령벌 MDF 시멘트 복합재료의 미세조직 변화를 살펴보았다. 적량의 epoxy resin 첨가에 의해 건조강도는 감소하였으나 전반적으로 수분안정성이 향상되었다. 그러나 전반적으로 epoxy의 함량이 많아지면 초기건조강도는 감소하는 경향을 나타나었으며 epoxy 첨가량이 7wt% 이상일 경우에서는 수분안정성 역시 별다른 효과를 볼 수 없었다. 제조공정별로는 warm pressing법에 의해 성형된 경우 epoxy 첨가에 의한 강도 및 수분안정성 향상 효율이 다른 방법보다 월등히 뛰어났으며 epoxy resinmdmf 5wt%, 7wt% 첨가하였을 때, 최적의 강도 및 수분안정성 효과를 얻을 수 있었다.

• Child Health Nursing Research
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• 제11권4호
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• pp.390-395
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• 2005

Purpose: To investigate the effects of a warm water-filled bag on body temperature, Oxygen demand, respiratory rate and blood sugar in high risk neonates. Method: The infants were assigned to two groups, 16 in the experimental and 20 in the control group. Infants in the experimental group was received $40{\~}42^{\circ}C$ warm water-filled bag therapy for 2 hours under radiant warmers. Infants in the control group were placed under the same kind of radiant warmers but without the warm water-filled bag. The following were measured every 30 minutes: rectal temperature, $O_2$ demand ($FiO_2$), and respiratory rate. Blood sugar was measured hourly. Result: Body temperatures increased significantly in the experimental group (P=0.0138), and there was a difference according to time (P=0.0001). Significant difference were found between the two groups fur $FiO_2$ (P=0.0180). There was no difference in respiratory rates between the two groups and rates according to time for the experimental group were also not significant (P=0.3569). No significant difference between two groups was found for blood sugar (P=0.2152), but there was a significant difference according to the times (P=0.0001). Conclusion: This results of this study indicate that a warm-filled bag is an effective means of resorting body temperature and reducing $O_2$ demand in high risk neonates.