• Journal of Soil and Groundwater Environment
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• v.22 no.4
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• pp.9-26
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• 2017

When a warm well located downgradient is captured by cold thermal plume originated from an upgradient cold well, the warm thermal plume is pushed further downgradient in the direction of groundwater flow. If groundwater flow direction is parallel to an aquifer thermal energy storage (ATES), the warm well can no longer be utilized as a heat source during the winter season because of the reduced heat capacity of the warm groundwater. It has been found that when the specific discharge is increased by $1{\times}10^{-7}m/s$ in this situation, the performance of ATES is decreased by approximately 2.9% in the warm thermal plume, and approximately 6.5% in the cold thermal plume. An increase of the specific discharge in a permeable hydrogeothermal system with a relatively large hydraulic gradient creates serious thermal interferences between warm and cold thermal plumes. Therefore, an area comprising a permeable aquifer system with large hydraulic gradient should not be used for ATES site. In case of ATES located perpendicular to groundwater flow, when the specific discharge is increased by $1{\times}10^{-7}m/s$ in the warm thermal plume, the performance of ATES is decreased by about 2.5%. This is 13.8% less reduced performance than the parallel case, indicating that an increase of groundwater flow tends to decrease the thermal interference between cold and warm wells. The system performance of ATES that is perpendicular to groundwater flow is much better than that of parallel ATES.

• Korean Journal of Applied Biomechanics
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• v.31 no.4
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• pp.297-307
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• 2021

Objective: The aim of this study was to analyze kinetic variables between thermotherapy and dynamic warm-up during drop-landing. Method: Twenty male healthy subjects (Age: 21.85 ± 1.90 years, Height: 1.81 ± 0.06 cm, Weight: 68.5 ± 7.06 kg) underwent three treatments applied on the thermotherapy of femoral muscles and a dynamic warm-up. The thermotherapy was performed for 15 minutes while sitting in a chair using an electric heating pad equipped with a temperature control device. Dynamic warm-up performed 14 exercise, a non-treatment was sitting in a chair for 15 minutes. Core temperature measurements of all subjects were performed before landing at a height of 50 cm. During drop-landing, core temperature, joint angle, moment, work of the sagittal plane was collected and analyzed. All analyses were performed with SPSS 21.0 and for repeated measured ANOVA and Post-hoc was Bonferroni. Results: Results indicated that Thermotherapy was increased temperature than other treatments (p = .000). During drop-landing, hip joint of dynamic warm-up was slower for angular velocity (p < .005), and left ankle joint was fastest than other treatments (p = .004). Maximum joint moment of dynamic warm-up was smaller for three joints (hip extension: p = .000; knee flexion/extension: p = .001/.000; ankle plantarflexion: p = .000). Negative work of dynamic warm-up was smaller than other treatments (p = .000). Conclusion: In conclusion, the thermotherapy in the local area doesn't affect the eccentric contraction of the thigh. The dynamic warm-up treatment minimized the joint moment and negative work of the lower joint during an eccentric contraction, it was confirmed that more active movement was performed than other treatment methods.

• The Journal of Korean Obstetrics and Gynecology
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• v.29 no.3
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• pp.57-67
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• 2016

Objectives: This paper was aim to report the effects of Sobokchukeo-tang-gagambang and warm needle therapy on the dysmenorrhea patients.Methods: The patients having treated with Sobokchukeo-tang-gagambang and warm needle therapy, from January 1st in 2014 until May 31st in 2016, was enrolled in this study. We collected and analyzed their age, accessory complaint except dysmenorrhea, treatment period, dosage of herbal medicine, diagnosed gynecological disease, remedies’ effectiveness, etc.Results: All of the patients treated with Sobokchukeo-tang-gagambang and warm needle therapy in this study were recovered. Also, correlation between the characteristic and recovery status of patients was not confirmed.Conclusions: Sobokchukeo-tang-gagambang and warm needle therapy is effective on patients having variable gynecological diseases. But the cases are very deficient, so we need to study about availability of Sobokchukeo-tang and warm needle therapy on dysmenorrhea more systematically.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.3 s.168
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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.

• Ocean and Polar Research
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• v.35 no.2
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• pp.127-134
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• 2013

In this study we investigated changes in the Tsushima Warm Current (TWC) under the global warming scenario RCP 4.5 by analysing the results from the World Climate Research Program's (WCRP) Coupled Model Intercomparison Project Phase 5 (CMIP5). Among the four models that had been employed to analyse the Tsushima Warm Current during the 20th Century, in the CSIRO-Mk3.6.0 and HadGEM2-CC models the transports of the Tsushima Warm Current were 2.8 Sv and 2.1 Sv, respectively, and comparable to observed transport, which is between 2.4 and 2.77 Sv. In the other two models the transports were much greater or smaller than the observed estimates. Using the two models that properly reproduced the transport of the Tsushima Warm Current we investigated the response of the current under the global warming scenario. In both models the volume transports and the temperature were greater in the future climate scenario. Warm advection into the East Sea was intensified to raise the temperature and consequently the heat loss to the air.

• Journal of Applied Reliability
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• v.18 no.1
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• pp.72-79
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• 2018

Purpose: Numerical and experimental study was performed to evaluate the effect of peening temperature on the residual compressive stress distribution and magnitude of residual compressive stress at the material surface. Methods: A compressive air-propelled warm peening equipment was designed and manufactured for warm peening test. Results: 3D dynamic finite element (FE) model of the warm peening test was proposed and validity of the proposed FE model was verified by comparing the predicted residual stresses with the measured residual stresses in the open literature. Maximum warm peening temperature and a proper peening time were investigated with the proposed FE model. Conclusion: Compressive residual stress increased remarkably with peening temperature increased. But, peening temperature is greater than $350^{\circ}C$, the effect of peening temperature disappeared. Therefore, maximum peening temperature possibly applicable for warm peening industry might be $350^{\circ}C$ and peening time is 45s.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.11
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• pp.1897-1906
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• 2003

A finite element analysis for near-net-shape forming of A16061 powder was performed under warm rubber isostatic pressing and warm die pressing. The advantages of warm compaction by rubber isostatic pressing were discussed to obtain a part with better density distributions. The shape of rubber mold was designed by determining a cavity shape that provides a desired shape of the final powder compact. To simulate densification and deformed shape of a powder compact during pressing, the elastoplastic constitutive equation based on yield function of Shima-Oyane was implemented into a finite element program(ABAQUS). The hyperelastic constitutive equation based on the Ogden strain energy Potential was employed to analyze nonlinear elastic response of rubber. Finite element results were compared with experimental data for Al6061 powder compacts under warm die pressing and warm isostatic pressing.

• Ocean and Polar Research
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• v.31 no.4
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• pp.283-296
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• 2009

Oceanographic survey data were analyzed to understand the characteristics of a warm eddy observed in the Ulleung Basin in July 2005. The temperature distribution at 200 db and vertical sections provided evidence of the warm eddy in the Ulleung Basin (UWE05). Based on the 5$^{\circ}C$ isothermal line on 200 db temperature, the major axis was 160 km from southwest to northeast, and the minor axis was 80 km from southeast to northwest. The homogeneous layer in the thermocline of UWE05 had mean values of 10.40$^{\circ}C$ potential temperature, 34.35 psu salinity, and 26.37 kg/m$^3$ potential density (${\sigma}_{\theta}$) and provided evidence that UWE05 also existed during the winter of 2004-2005. A warm streamer initially flowed along the circumference of UWE05 and mixed with the upper central water. Two northward current cores were found on the western side of the measured current section at the central latitude of UWE05. One was the East Korean Warm Current (EKWC) and the other was the main stream of the western part of UWE05. Geostrophic transport of the upper layer (from the surface to the isopycnal surface of 26.9 ${\sigma}_{\theta}$) was approximately 2.5 Sv in the eastern side of UWE05. However, the measured transport was twice as large as the geostrophic transport. Mass conservation of geostrophic transport was well satisfied in the upper layer. The direct current measurements and geostrophic transport analysis showed that the EKWC meandered around UWE05.

• Transactions of Materials Processing
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• v.15 no.2 s.83
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• pp.148-152
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• 2006

In this study, the experiments of warm deep drawing were done with heated die, and with heated die, and blankholder, and cooled punch in order to investigate the formability of AZ31 magnesium alloy sheet in warm deep drawing. For this, warm deep drawing experiments were executed under various temperatures and punch velocities. The results of warm deep drawing with heated die showed that fracture occurred around the punch part at punch velocity of 75mm/min and punch stroke of 10mm under temperature range of 373-523K, but did not occur under temperature range of 548-673K even punch stroke of 25mm. And fracture at the punch stroke of 25mm and the temperature of 523K did not occur under the punch velocity of 30mm/min, but occurred under punch velocity of 75 and 125mm/min. Also warm deep drawing with heated die and blankholder, and cooled punch showed that the temperature range happening maximum height under punch velocity of 10-100mm/min was around 498-523K. Finally, with heating and cooling technique necking of AZ31 magnesium alloy occurred at punch shoulder part under the temperature range of 293-423K, but at die wall part under the temperature range of 473-573K.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.377-380
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• 2005

In this study, the experiments of warm deep drawing were done with heated die, and with heated die and cooled punch in order to investigate the formability of ZA31 magnesium sheet alloy of warm deep drawing. For this, warm deep drawing experiments were executed under various temperature, punch velocity and blankholder force. The results of warm deep drawing with heated die showed that fracture occurred punch part at punch velocity of 75mm/min and punch stroke of 10mm under temperature of $100^{\circ}C\~250^{\circ}C$, but did not occure under temperature of $275^{\circ}C\~400^{\circ}C$. And fracture at punch stroke of 25mm did not occurre at punch part under punch velocity of 30mm/min and $250^{\circ}C$, but occured under punch velocity of 75 and 125 mm/min. Also the results of warm deep drawing with heated die and cooled punch showed that the temperature happening maximum height under punch velocity of 10-100mm/min was $225-250^{\circ}C$. And necking occurred at punch shoulder under $20\~150^{\circ}C$, but at die wall under $200\~300^{\circ}C$.