• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.555-559
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• 2008

Junction temperature of quantum dot laser diodes is investigated by utilizing forward voltage-temperature method. In the case of ridge type laser diodes with deep mesa the increasing rate of junction temperature to current is about 0.05 K/mA, while in the case of shallow mesa the increasing rate is about 0.07 K/mA. It is explained that the relatively low increasing rate in the deep mesa results from the heat expansion to the lateral direction of mesa.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.4
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• pp.31-36
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• 2015

The demand for multi-functionality, high density, high performance, and miniaturization of IC devices has caused the technology paradigm shift for electronic packaging. So, thermal management of new packaged chips becomes a bottleneck for the performance of next generation devices. Among various thermal solutions such as heat sink, heat spreader, TIM, thermoelectric cooler, etc. on-chip liquid cooling module was investigated in this study. Micro-channel was fabricated on Si wafer using a deep reactive ion etching, and 3 different micro-channel designs (straight MC, serpentine MC, zigzag MC) were formed to evalute the effectiveness of liquid cooling. At the heating temperature of $200^{\circ}C$ and coolant flow rate of 150ml/min, straight MC showed the high temperature differential of ${\sim}44^{\circ}C$ after liquid cooling. The shape of liquid flowing through micro-channel was observed by fluorescence microscope, and the temperarue differential of liquid cooling module was measuremd by IR microscope.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.652-656
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• 1997

This study was conducted to determine the relationships between abdominal temperature (Tabd) and some thermoregulatory responses, such as heat production (HP), heart rate (HR), respiration rate (RR), temperature of external ear tract (Tee), comb surface temperature (Tcs) and shank skin temperature (Tss), for revealing the role of deep body temperature in the thermoregulation of broiler chickens. Tabd was divided into 5 zones of 40-41, 41-42, 42-43, 43-44 and $44-45^{\circ}C$, and maintained for 3 hours in each zone by varying environmental temperature from 11 to $33^{\circ}C$. HP and HR had a greater increase with Tabd above $42.5^{\circ}C$. RR increased markedly with Tabd above $41.5^{\circ}C$, and reached a maximum when Tabd was at $42.5^{\circ}C$, then began to decrease. In addition, HP and HR increased significantly with decrease RR during the decreasing phase of panting. Tcs and Tss changed rapidly with Tabd when Tabd was below $41.5^{\circ}C$, and increased more slowly above $41.5^{\circ}C$. Tee was lower than Tabd, and its increase was less than that of Tabd. These results suggest that changes in thermoregulatory responses are induced by an increase in abdominal temperature. Tabd increases to adjust the ratio of sensible and evaporative heat loss when Tabd is below $42.5^{\circ}C$, while the ability in body temperature regulation gradually disappears when abdominal temperature exceeds $42.5^{\circ}C$ and heat balance can not be maintained.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.12
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• pp.1055-1060
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• 2016

Laser welding is a high-density energy welding method. Hence, deep penetration and high welding speed can be realized with lower heat input as compared with conventional welding. The heat input of a CW laser welding is determined by laser power and welding speed. In this study, bead and lap welding of $0.5mm^t$ pure titanium was performed using a fiber laser. Its weldability with laser power and welding speed was evaluated. Penetration, bead width, joining length, and bead shape were investigated, and the mechanical properties were examined through tensile-shear strength tests. Welds with sound joining length were obtained when the laser power and welding speed were respectively 0.5 kW and 2.5 m/min, and 1.5 kW and 6 m/min, and the weld obtained at low output presented better ductility than that obtained at high output.

• Journal of Oriental Physiology
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• v.14 no.2 s.20
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• pp.23-41
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• 1999

The disease of cholelith is common world widely. As life expectancy gets extended and life environment and dietary life change, increased to gallstone in Korea. On the case that elimination surgery is inapplicable and for the aged patients. recently the dissolution therapy of cholelith is studied world widely. From the view of oriental medicine, the causes of gallstone, treatment methods and the effects of therapy are as follows ; 1. The attack of gallstone is by the stagnation and disturbance of qi in the body. 2. The causes of gallstone are classified into three types. 1).The type of stagnation of qi. 2).The type of damp-heat. 3).The type of noxious heat. 3. The treatment effect is high in the damp-heat type. 4. Medical treatment of gallstone, considering the function of the intestines, are lithodialysis and removol of gallstone, soothing the liver and regulating the cerculation of qi, clearing away heat and elininating dampness. 5. The dissolution therapy of gallstone effected to the size within the diameter of 1.5cm 6. Through the oriental medicine therapy, besides excretion and dissolution of gallstone, the interval extention and elimination of spasm, the prevention of relapse and aftere effect are to be expected. The study which can improve the treatment rate of cholelith through the combination therapy of oriental and western is needed and deep study on oriental medicine diagnostic and classification according to the observation based on symptoms is necessary.

• The Journal of Engineering Geology
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• v.33 no.4
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• pp.673-687
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• 2023

Exploratory data analysis is the process of observing and understanding data collected from various sources to identify their distributions and correlations through their structures and characterization. This process can be used to identify correlations among conditioning factors and select the most effective factors for analysis. This can help the assessment of landslide susceptibility, because landslides are usually triggered by multiple factors, and the impacts of these factors vary by region. This study compared two stages of exploratory data analysis to examine the impact of the data exploration procedure on the landslide prediction model's performance with respect to factor selection. Deep-learning-based landslide susceptibility analysis used either a combinations of selected factors or all 23 factors. During the data exploration phase, we used a Pearson correlation coefficient heat map and a histogram of random forest feature importance. We then assessed the accuracy of our deep-learning-based analysis of landslide susceptibility using a confusion matrix. Finally, a landslide susceptibility map was generated using the landslide susceptibility index derived from the proposed analysis. The analysis revealed that using all 23 factors resulted in low accuracy (55.90%), but using the 13 factors selected in one step of exploration improved the accuracy to 81.25%. This was further improved to 92.80% using only the nine conditioning factors selected during both steps of the data exploration. Therefore, exploratory data analysis selected the conditioning factors most suitable for landslide susceptibility analysis and thereby improving the performance of the analysis.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.1
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• pp.80-87
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• 2001

Global robust diagnostic models are established based on MOM of GFDL to study the circulation in the world ocean. The horizontal grid sizes 1/2 degree, and the vertical water column is divided into 21 levels. The hydrographic data are taken from Levitus et al.(1994) and the wind stress from Hellerman and Rosenstein (1983). Based on the model results the horizontal volume, heat and salt transports across some representative sections are calculated. The preliminary results show that Though the cross-equator volume transports in the Atlantic, Indian and Pacific Oceans are all small, the heat transports across equator in the Atlantic are northward. This is clearly a result of the southward flow of the North Atlantic Deep Water and the northward compensating warm flow in the upper layer. The annual mean of the cross-equator heat transport in the Pacific Ocean from the present model is significantly lower than that calculated by Philander et at. (1987). This might indicate the importance of the Indonesian Throughflow in the heat transport in the Pacific Ocean. Our calculation shows that the heat transport through the Indonesian Archipelago is 0.5 PW, which is comparable with the poleward heat transport in the North Atlantic and Pacific Oceans. The difference in heat transports across the sections 5 and 6 demonstrates the important role of the Agulhas Current in the heat balance of the world ocean.

• Journal of the Korean Society of Systems Engineering
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• v.12 no.1
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• pp.73-87
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• 2016

Combining power generation and water production by desalination is economically advantageous. Most desalination projects use fossil fuels as an energy source, and thus contribute to increased levels of greenhouse gases. Environmental concerns have spurred researchers to find new sources of energy for desalination plants. The coupling of nuclear power production with desalination is one of the best options to achieve growth with lower environmental impact. In this paper, we will per-form a sensitivity study of coupling nuclear power to various combinations of desalination technology: {1} thermal (MSF [Multi-Stage Flashing], MED [Multi-Effect Distillation], and MED-TVC [Multi-Effect Distillation with Thermal Vapour Compression]); {2} membrane RO [Reverse Osmosis]; and {3} hybrid (MSF-RO [Multi-Stage Flashing & Reverse Osmosis] and MED-RO [Multi-Effect Distillation & Reverse Osmosis]). The Korean designed reactor plant, the APR1400 will be modeled as the energy production facility. The economical evaluation will then be executed using the computer program DEEP (Desalination Economic Evaluation Program) as developed by the IAEA. The program has capabilities to model several types of nuclear and fossil power plants, nuclear and fossil heat sources, and thermal distillation and membrane desalination technologies. The output of DEEP includes levelized water and power costs, breakdowns of cost components, energy consumption, and net saleable power for any selected option. In this study, we will examine the APR1400 coupled with a desalination power plant in the Kingdom of Saudi Arabia (KSA) as a prototypical example. The KSA currently has approximately 20% of the installed worldwide capacity for seawater desalination. Utilities such as power and water are constructed and run by the government. Per state practice, economic evaluation for these utilities do not consider or apply interest or carrying cost. Therefore, in this paper the evaluation results will be based on two scenarios. The first one assumes the water utility is under direct government control and in this case the interest and discount rate will be set to zero. The second scenario will assume that the water utility is controlled by a private enterprise and in this case we will consider different values of interest and discount rates (4%, 8%, & 12%).

• Journal of the Korean Society for Precision Engineering
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• v.15 no.10
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• pp.65-72
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• 1998

The BTA drilling chip is better for deep hole drilling than other self-piloting with pad drilling chips because the large length to diameter ratio allows a unique cutting force dispersion and better supplies the high pressure fluid. Therefore the BTA is useful for many tasks, such as coolant hole drilling of large scale dies, as well as tube seat drilling, which is essential for the heat exchanger, and variable component drilling for automobiles. Deep hole drilling has several significant problems, such as hole deviation, hole over-size, circularity, straightness, and surface roughness. The reasons for these problems, which often result in quality short comings, are an alignment of the BTA drilling system and the unbalance of cutting force by work piece and tool shape. This paper analyzes the properties through an experiment which com¬pared single-edge BTA drills with multiple-edge BTA drills, as well as the shapes of the tools to cause an unbalance of cutting force, and its effect on the precision of the worked hole. Conclusions are as follows. 1) In SMSSC drilling, 60m/min of BTA with single and multi-edged tools proved the best cutting condition and the lowest wear character. 2) The roundness got a little worse as cutting speed was increased, but surface roughness was hot affected. 3) It was proved that the burnishing torque of both drills approached 26%. which is almost the same as the 24% insisted on by Griffiths, and the dispersion characteristic of the multi-edged BTA drill proved better than the single-edge BTA drill.

• The Journal of Korean Medicine
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• v.42 no.2
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• pp.107-119
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• 2021

Objectives: This study was aimed to report changes in clinical symptoms and signs after treatment with Korean medicine in patients who suffered from calf edema due to deep vein thrombosis (DVT). Methods: A 46-year-old male patient, who discharged home after receiving standardized treatment for acute DVT in the right leg, suffered pain and heat sense due to edema of the affected calf. Oral administration of herbal medicine (Gyejibongnyeong-hwan 4 g, twice daily) and acupuncture therapy were given to him for 6 weeks. The change in chief complaints, Villalta score, the right and left side difference of the circumference and the skin surface temperature of both calves, and blood level of D-dimer were observed before and after treatment. Results: The patient's chief complaints began to significantly improve from 2 weeks after treatment, and disappeared completely within 4 weeks. At the end of the treatment, a substantial decrease in the difference between the right and left calves in the circumference and skin surface temperature was observed. This effect was maintained even at the time of follow-up 3 months after the end of treatment, and the patient completely recovered indoor and outdoor life to the level before onset. Conclusions: This case suggests that Korean medicine treatment, including Gyejibongnyeong-hwan administration and acupuncture therapy, can be a viable option to improve edema and related clinical problems in the affected limbs due to DVT.