• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.1019-1030
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• 1994

Natural convection heat transfer from a horizontal ice cylinder immersed in quiescent cold pure water was studied experimentally. The experiment was conducted for the ambient water temperatures ranging from $2.0^{\cric}C$ to $10.0^{\circ}C$. The flow fields around an ice cylinder and its melting shapes were visualized and local Nusselt numbers obtained. Especially, its attention was focused on the density maximum effects and stagnation point Nusselt number. From the visualized photographs of flow fields, three distinct flow patterns were observed with the ambient water temperature variation. The melting shapes of ice cylinder are various in shape with flow patterns. Steady state upflow was occured at the range of $2.0^{\circ}C \leq T_{\infty} \leq 4.6^{\circ}C$ and steady state downflow was occured at $T_{\infty} \geq 6.0^{\circ}C$. In the range of $4.7^{\circ}C < T_{\infty} < 6.0^{\circ}C$, three-dimensional unsteady state flow was observed. Especially, the melting shapes of ice cylinder have formed the several spiral flutes for the temperatures ranging from $5.5^{\circ}C$ to $5.8^{\circ}C$. For upflow regime, the maximum stagnation point Nusselt number exists at $T_{\infty} = 2.5^{\circ}C$ and as the ambient water temperature increases the Nusselt number decreases. At ambient water temperature of about $5.7^{\circ}C$, Nusselt number shows its minimum value.

• Plant Biotechnology Reports
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• v.3 no.3
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• pp.183-190
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• 2009

Rho-related GTPase of plants (ROP) plays an important role in plant growth and development as a signaling protein. Plant RopGEFs are recently identified ROP activator proteins in Arabidopsis. In this study, we cloned 14 RopGEFs in Arabidopsis and characterized their expression patterns in response to abiotic stresses. Fourteen RopGEF genes were categorized into three groups based on their amino acid homologies and molecular sizes. Most RopGEFs were expressed predominantly in flower but some RopGEFs displayed a tissue-specific expression pattern. RopGEF1, 4, 5, and 11 were expressed in all tissues including root and leaves whereas RopGEF7, 8, 9, and 13 were expressed only in flowers. The transcript levels of 14 RopGEFs were changed significantly depending upon abiotic stresses such as cold, heat, drought and salts. RopGEF5 transcription was up-regulated by salt and drought treatment but down-regulated by heat. RopGEF14 transcript level was also increased by salt but decreased by heat stress. The transcript levels of RopGEF1, 7, 9, and 12 were enhanced in response to heat stress but showed no changes in response to cold stresses. Drought stress activated Group 3 RopGEFs such as RopGEF5 and 7. Taken together, 14 RopGEFs are responding to the abiotic stresses individually or as a group.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.218-233
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• 2022

The long-term (1986~2020) predictability of the number of days of heat and cold damages for each growth stage of soybean is evaluated using the daily maximum and minimum temperature (Tmax and Tmin) data produced by Pusan National University Coupled General Circulation Model (PNU CGCM)-Weather Research and Forecasting (WRF). The Predictability evaluation methods for the number of days of damages are Normalized Standard Deviations (NSD), Root Mean Square Error (RMSE), Hit Rate (HR), and Heidke Skill Score (HSS). First, we verified the simulation performance of the Tmax and Tmin, which are the variables that define the heat and cold damages of soybean. As a result, although there are some differences depending on the month starting with initial conditions from January (01RUN) to May (05RUN), the result after a systematic bias correction by the Variance Scaling method is similar to the observation compared to the bias-uncorrected one. The simulation performance for correction Tmax and Tmin from March to October is overall high in the results (ENS) averaged by applying the Simple Composite Method (SCM) from 01RUN to 05RUN. In addition, the model well simulates the regional patterns and characteristics of the number of days of heat and cold damages by according to the growth stages of soybean, compared with observations. In ENS, HR and HSS for heat damage (cold damage) of soybean have ranged from 0.45~0.75, 0.02~0.10 (0.49~0.76, -0.04~0.11) during each growth stage. In conclusion, 01RUN~05RUN and ENS of PNU CGCM-WRF Chain have the reasonable performance to predict heat and cold damages for each growth stage of soybean in South Korea.

• The Journal of Internal Korean Medicine
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• v.39 no.4
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• pp.495-510
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• 2018

Objective: This study was designed to investigate the possibility of quantification of the diagnosis of abdominal coldness (AC) in patients with functional dyspepsia (FD). Methods: Forty-four patients with FD were enrolled in this study. Three Korean medicine doctors each randomly examined all abdomens. Diagnosis of AC was made by consensus of at least two of the doctors. Body temperature (oral by digital oral thermometer) and skin temperature (by digital infrared thermal imaging [DITI]) were measured, followed by administration of the Cold and Heat questionnaire (CHQ) and the Instrument of Pattern Identification for Functional Dyspepsia (IPIFD). Results: Of the 44 patients with FD, 22 were assigned to the AC group and 22 to the non-AC group. The concordance rate of diagnosis among the three doctors was 63.6% (28/44), with a ${\kappa}$ of 0.504, indicating means moderate agreement). Neither the oral nor the skin temperatures showed statistically significant differences between the AC and non-AC groups. However, the CHQ scores and 'Simultaneous Occurrence of Cold and Heat Syndromes pattern' scores of the IPIFD were higher in AC group and showed statistically significant differences (p=0.010 and 0.009). Conclusions: This is the first study conducting quantitative measurements of abdominal coldness in patients with FD. Although oral and skin temperature showed no statistical significance between AC and non-AC groups, the concordance rate of diagnosis of AC among the three Korean Medicine doctors was moderate. The CHQ scores and 'Simultaneous Occurrence of Cold and Heat Syndromes pattern' scores of the IPIFD also suggest that diagnosis of AC is relevant to cold and heat patterns, and these questionnaires could be utilized as supportive data for the diagnosis of AC. Further studies should be conducted for the purpose of quantifying and standardizing abdominal examinations in Korean Medicine.

• Journal of Sasang Constitutional Medicine
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• v.24 no.4
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• pp.28-39
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• 2012

Objectives : This study is aimed to develop the algorithm to diagnose Taeeumin's symptomology, by the method of literature research on Sasang Constitutional Medicine. Methods : Applying the sequential differentiations of Taeeumin's symptomology, or exterior-interior disease differentiation, favorable-unfavorable pattern differentiation, and mild-severe-dangerous-urgent pattern differentiation, "Donguisusebowon" and related literatures have been reviewed. Results and Conclusions : 1) 1st step: Taeeumin's exterior pattern and interior pattern are differentiated by the indexes of whole-body cold or heat pattern, sweating, and facial complexion. 2) 2nd step: The favorable pattern of the Taeeumin's exterior disease can be detected by indexes of the existence of fever, generalized pain while the unfavorable one by indexes of the abnormal condition of digestion and feces, and fearful throbbing. The favorable pattern of the Taeeumin's interior disease can be diagnosed based on indexes of eye pain, dry nose, dry throat, and heat symptoms that occur in various parts of the body, while the unfavorable one by indexes of thirsty, urination, feces and specific symptoms which can be induced by dryness. And in the both unfavorable patterns the dark complexion on the faces is revealed. 3) 3rd step: The mild-severe patterns of the favorably exterior disease are differentiated in terms of the condition of fever, while the mild-severe patterns of the favorably interior disease are in differentiated based on whether abnormal symptoms are revealed in the gastrointestinal tract. Both of the unfavorably dangerous-urgent patterns in exterior and interior diseases are differentiated by the symptoms such as tinnitus, dim vision, weakness of legs and back pain, and lack of strength in legs and thighs.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.30 no.4
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• pp.175-185
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• 2018

This research investigates the internal flow and heat transfer in a plate heat exchanger with chevron shape by utilizing the computational fluid dynamics (CFD) software. The basic unit of the plate heat exchanger is generally composed of a hot channel, an intermediate chevron plate, and a cold channel. Several studies have reported experimental and numerical simulation of heat transfer and pressure drop. This study focused on the detailed numerical simulation of flow and heat transfer in the complicated chevron shape channel. The long chevron plate was designed to include 16 chevron patterns. For proper mesh resolution, the number of cells was determined after the grid sensitivity test. The working fluid is water, and its properties are defined as a function of temperature. The Reynolds number ranges from 900 to 9,000 in the simulation. A realizable $k-{\varepsilon}$ model and non-equilibrium wall function are properly considered for the turbulent flow. The friction factors and heat transfer coefficient are validated by comparing them with existing empirical correlations, and other patterned flow phenomena are also investigated.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.2
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• pp.85-94
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• 2013

Objectives : This study aims to contribute to developing new pattern identification based on searches regarding pattern identification of low back pain, which is used in thesis both in Korea and China. Methods : First of all, we searched thesis concerning pattern identification of low back pain from RISS, OASIS, Korean traditional knowledge portal, CNKI. Results : 1. There were overall 34 thesis, consist of 18 Korean thesis(13 clinical papers and 5 analytical papers) and 9 Chinese thesis(7 clinical papers and 9 analytical papers). 2. 10 of 11 Korean thesis used more than 9 patterns for pattern identification, 9 of 14 Chinese thesis used less than 4 patterns for pattern identification of low back pain. 3. Patterns, which were repeatedly used in Korea, were 腎虛腰痛(Kidney deficiency low back pain), 濕熱腰痛(Dampness-heat low back pain), 寒濕腰痛(Cold-dampness low back pain), 痰飮腰痛(Phlegm-fluid retention low back pain), 風腰痛(Wind low back pain), 食積腰痛(Food accumulation low back pain), 濕腰痛(Dampness low back pain), 挫閃腰痛(Sprain low back pain), 瘀血腰痛(Static blood low back pain), 氣腰痛(Qi low back pain). 4. Patterns, which were repeatedly used in China, were 腎虛腰痛(Kidney deficiency low back pain), 濕熱腰痛(Dampness-heat low back pain), 寒濕腰痛(Cold-dampness low back pain), 氣滯血瘀腰痛(Blood stasis due to qi stagnation low back pain). Conclusions : Based on these results, it is considered that an advanced type of pattern identification of low back pain should be made or existing type needs to be practically and objectively improved.

• Journal of Biomedical Engineering Research
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• v.23 no.6
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• pp.467-475
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• 2002

Hyperthermia using transrectal thermal probes has been used for a noninvasive treatment of prostate diseases. However it is known that heating the rectal wall at excessively high temperature can lead to destruction of the rectal mucous membrane. and it is difficult to maintain an optimum temperature over the entire prostate. Thus, a more accurate understanding of the heat transfer mechanism between prostate and hyperthermia system is needed Numerical analysis was performed to investigate how the cold/warm stimulations on the prostate surface affect the temperature distribution in the prostate model. The general purpose software "FLUENT" was used for obtaining a finite volume solution to the unsteady conduction equation and to calculate the time-varying temperature in the prostate. Effects of the warm/cold stimulations and the stimulation frequency on the temperature distribution were simulated. and we visualized how hyperthermia affected the inside of the prostate. It was found that the effect of hyperthermia by using a typical heating method is limited due to the low thermal conductivity of the prostate. Consecutive repetitions of warm and cold stimulations were considered to provide the thermal irritations inside a prostate. The effects of temperature difference and duration of warm/cold stimulations were investigated, and basic data for the optimum period and effective patterns of stimulations were obtained. A simplified bioheat equation was also solved to describe effects of the blood flow on the blood-tissue heat transfer. The effect of blood flow was not dominant compared to that of warm/cold stimulations. These results might be used as data for design of prostate treating probe, prostatic therapy and thermal stimulation effects on the prostate.

• Journal of Environmental Impact Assessment
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• v.20 no.3
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• pp.299-311
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• 2011

The objective of this paper is to present a methodology for the classification of spatial patterns considering the parameters of urban form which play a significant role in the formation of the urban climate. The urban morphological parameters, i.e. building coverage, impervious pavement, vegetation, water, farmland and landuse types were used to classify the spatial patterns by a K-means cluster analysis. And the presented methodology was applied on Changwon city, South Korea. According to the results of cluster analysis, the total spatial patterns were classified as 24 patterns. First of all, The spatial patterns(A-1, A-2, A-3, B-1, B-2, B-3, C-1, C-2, C-3, D-1, D-2, D-3, E-1, E-2, E-3, F-1, F-2, F-3, G-1, G-2, G-3), which distributed in the rural area and the suburban area, can have the positive impacts of cold air generation and wind corridor on an urban climate environment, were distributed in the rural area. On the other hand, the spatial patterns of the downtown area including A-4, B-4, C-4 and D-4 are expected to have the negative impacts on urban climate owing to the of artificial heat emission or the wind flow obstruction. Finally, it will require the future research to analysis the climatic properties according to the same spatial patterns by the field survey.

• Atmosphere
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• v.29 no.4
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• pp.451-461
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• 2019

Medium-range forecast is highly dependent on ensemble forecast data. However, operational weather forecasters have not enough time to digest all of detailed features revealed in ensemble forecast data. To utilize the ensemble data effectively in medium-range forecasting, representative weather patterns in East Asia in this study are defined. The k-means clustering analysis is applied for the objectivity of weather patterns. Input data used daily Mean Sea Level Pressure (MSLP) anomaly of the ECMWF ReAnalysis-Interim (ERA-Interim) during 1981~2010 (30 years) provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). Using the Explained Variance (EV), the optimal study area is defined by 20~60°N, 100~150°E. The number of clusters defined by Explained Cluster Variance (ECV) is thirty (k = 30). 30 representative weather patterns with their frequencies are summarized. Weather pattern #1 occurred all seasons, but it was about 56% in summer (June~September). The relatively rare occurrence of weather pattern (#30) occurred mainly in winter. Additionally, we investigate the relationship between weather patterns and extreme weather events such as heat wave, cold wave, and heavy rainfall as well as snowfall. The weather patterns associated with heavy rainfall exceeding 110 mm day^-1 were #1, #4, and #9 with days (%) of more than 10%. Heavy snowfall events exceeding 24 cm day^-1 mainly occurred in weather pattern #28 (4%) and #29 (6%). High and low temperature events (> 34℃ and < -14℃) were associated with weather pattern #1~4 (14~18%) and #28~29 (27~29%), respectively. These results suggest that the classification of various weather patterns will be used as a reference for grouping all ensemble forecast data, which will be useful for the scenario-based medium-range ensemble forecast in the future.