• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.9
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• pp.1060-1067
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• 1988

In this paper, we have investigated the effects of rapid thermal process on the electrical and structural properties of silicon films. It was shown that required times and temperature for the successful activation of dopants (Boron, Phosphorus:5E15atoms/cm\ulcorner were above 1000\ulcorner, 10sec, respectively. The typical resistivities of films deposited below 600\ulcorner were in the range of 1.0 E-3ohm-cm which was 20-30% lower than that of initially polycrystalline silicon depositd above 600\ulcorner. After rapid thermal process at high temperature above 1000\ulcorner, the films did not reveal any change in resistivity due to the dopant segregation, and better electrical conductivity could be obtained by increasing the process time. The grain growth by RTA treatment was more salient in the case of the doped amorphous than that of initially polycrystalline. The surface of the films also preserved the higher structural perfection and surface smoothness.

• Transactions of the KSME C: Technology and Education
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• v.1 no.2
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• pp.179-186
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• 2013

Far-infrared radiation therapies are becoming more popular for blood circulation disorders, cardiovascular disease, skin diseases, inhibit cancer cell, etc replacing conventional operations. In this research, thermal characteristics of heating part in panel radiators, which is effective on the blood circulation disorders were experimentally analyzed. The heating line supplies heat energy to insulation coatings with heat flux of $150mW/m^2$ in normal status and as a result the coatings reached 20% of the heating line temperature. In other words, the insulation itself could increase surface temperature of heating plates by 20% and raise thermal time constant promote blood circulation effect. We also found that space arrangement of the heating lines was an important factor in designing heating parts and both coefficient of heat conduction and density of the heating plate should be also considered for superimpose of thermal diffusion.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.495-498
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• 2004

PDP use the mixture of inert gases to generate a discharge inside display pixels. Inside of PDP, there exist highly reactive conditions in the gap between two glass panels. MgO layer and phosphor have been investigated as a function of discharge and thermal process. Impurities such as CO, $CO_2$, OH and $H_2O$ in discharge region may deteriorate the characteristics of PDP operation during life time. Change of impurity generation of various MgO and phosphor surfaces were measured by using x-ray photoelectron spectroscopy(XPS) and quadropole mass spectrometer (QMS). Carbon containing species such as C, CO and $CO_2$ were drastically increased on the surfaces during discharge and thermal treatment. Carbon impurities on the MgO and phosphor are the dominant factor for their instability.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.140-146
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• 2004

Objectives : this study is to see if there is a significance in thermal differences of acupoints in diagnosis and treatment period of facial paralysis and to substantiate the validity of acupuncture and moxibustion treatment for it. Methods : 1. By using DITI, thermal differences of acupoints on the face and the upper limbs of 13 Bell's palsy patients were measured around 3 days after an attack of the disease. These 13 patients, whose treatment progress was monitored up to 6 months after attack, were among the inpatients and outpatients of oriental internal medicine of National Medical Center from July 1 to August 31. 2. The patients were divided into 1month, 2-3months, 4months, 6months groups according to the occasion of improvement and thermal averages of each treatment period measured. Results : When it takes within 1 month for the condition of facial paralysis to change for the better, DITI image shows the temperature of the affected face parts and arms is higher than that of the non-affected parts. However, when it takes more than 4 months, the temperature of the affected face parts and arms on DITI image is lower than that of the non-affected parts. Conclusions : Hereby, prognosis of the disease and necessary time for the treatment can be presumed through DITI screening after an occurrence of facial paralysis. Also, condition of the disease is reflected by thermal differences of acupoints for Bell's palsy treatment that are in accordance with the theory of meridian on the face. This supports the efficacy of acupuncture and moxibustion treatment for this disease.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.8
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• pp.1062-1068
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• 2000

The effect of heat exchanger surface treatment on the frosting/defrosting behavior in a fin-tube heat exchanger is investigated experimentally. It is found that the hydrophilic surface mainly influences on the frosting behavior, however, the hydrophobic surface gives some influence on the defrosting behavior. In view of frosting performance, surface-treated heat exchanger with either hydrophilic or hydrophobic characteristic shows a little improvement in the thermal performance than the aluminium heat exchanger with no surface treatment. The result reveals that the heat exchanger with hydrophobic surface treatment is more effective in view of the defrosting efficiency and time. The amounts of residual water on the surface-treated heat exchangers are shown to be smaller than those of the bare heat exchanger, therefore further improvements on the performance of re-operations are expected.

• Journal of Surface Science and Engineering
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• v.48 no.6
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• pp.260-268
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• 2015

The thermal barrier coating (TBC) for inner wall of liquid-fuel rocket combustor consists of NiCrAlY as bonding layer and $ZrO_2$ as a top layer. In most case, the plasma spray coating is used for TBC process and this process has inherent possibility of cracking due to large difference in thermal expansion coefficients among bonding layer, top layer and metal substrate. In this paper, we suggest crack-free TBC process by using a precise electrodeposition technique. Electrodeposited Ni-P/Cr double layer has similar thermal expansion coefficient to the Cu alloy substrate resulting in superior thermal barrier performance and high temperature oxidation resistance. We studied the effects of phosphorous concentrations (2.12 wt%, 6.97 wt%, and 10.53 wt%) on the annealing behavior ($750^{\circ}C$) of Ni-P samples and Cr double layered electrodeposits. Annealing temperature was simulated by combustion test condition. Also, we conducted SEM/EDS and XRD analysis for Ni-P/Cr samples. The results showed that the band layers between Ni-P and Cr are Ni and Cr, and has no formed with heat treatment. These band layers were solid solution of Cr and Ni which is formed by interdiffusion of both alloy elements. In addition, the P was not found in it. The thickness of band layer was increased with increasing annealing time. We expected that the band layer can improve the adhesion between Cr and Ni-P.

• Clinics in Shoulder and Elbow
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• v.7 no.2
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• pp.76-82
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• 2004

Purpose: In the traumatic anterior shoulder instability, the laxity of joint capsule and ligament is frequently demonstrated. Although a arthroscopic procedure to address anterior instability with joint capsular redundancy have generally provided good results, its recurrence rate is higher than open procedure. By reducing the capsular redundancy, thermal shrinkage is likely to improve the outcome of arthroscopic anterior stabilization. The objective of this study was to evaluate additional thermal capsular shrinkage as a treatment of joint capsular redundancy in anterior shoulder instability. Materials and Methods: From March 1999 to June 2000, 25 shoulders of 23 patients of recurrent anterior shoulder dislocation underwent arthroscopic Bankart repair with shrinkage procedure. The mean follow up was 29 months and average age at the time of operation was 26 years. Of these patients, 20 were male and 3 were female who had been experienced the average 8 times of dislocation before operation. Thermal shrinkage alone without Bankart repair was performed in two cases who did not have Bankart lesion. The clinical result was evaluated in according to Modified Rowe Score. Results: The Modified Rowe Score was improved from preoperative 35 points to postoperative 88 points. None of cases showed recurrence of dislocation. But, in two cases, temporary sensory hypesthesia of the axillary nerve was developed and in two cases of postoperative stiffness, arthroscopic capsular release and brisement were performed. Conclusion: Additional capsular shrinkage in arthroscopic technique to address recurrent anterior shoulder instability could treat effectively the capsular redundancy.

• Journal of ILASS-Korea
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• v.24 no.4
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• pp.203-208
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• 2019

In general, the oxi-nitriding method is well known as such a surface treatment way for substantial enhancement in corrosion resistance, even comparable to that of titanium. However, there are still lacks of information on thermal performance of the oxi-nitriding surface being of additional compound layers on the base substrate. Above all, the quantitative measurement of its thermal performance still was not evaluated yet. Thus, the present study experimentally measures the thermal resistance of the oxi-nitriding surface during droplet evaporation and then estimates heat transfer performance with the use of the onedimensional heat transfer model in vertical direction. From the experimental results, it is found that the total evaporation time slightly increased with the thermal resistance caused by the oxi-nitriding layer, showing a maximum difference of approximately 20% with that of the bare surface. Although the heat transfer performance of oxi-nitriding surface became slightly lower than that of the bare surface, the oxi-nitriding surface exhibits much better heat transfer performance compared to titanium.

• Advances in materials Research
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• v.1 no.4
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• pp.245-268
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• 2012

Results of isothermal torsional oscillation tests are reported on melts of linear low density polyethylene and isotactic polypropylene. Prior to rheological tests, specimens were annealed at various temperatures ranging from $T_a$ = 180 to $310^{\circ}C$ for various amounts of time (from 30 to 120 min). Thermal treatment induced degradation of the melts and caused pronounced decreases in their molecular weights. With reference to the concept of transient networks, constitutive equations are developed for the viscoelastic response of polymer melts. A melt is treated as an equivalent network of strands bridged by junctions (entanglements and physical cross-links). The time-dependent response of the network is modelled as separation of active strands from and merging of dangling strands with temporary nodes. The stress-strain relations involve three adjustable parameters (the instantaneous shear modulus, the average activation energy for detachment of active strands, and the standard deviation of activation energies) that are determined by matching the dependencies of storage and loss moduli on frequency of oscillations. Good agreement is demonstrated between the experimental data and the results of numerical simulation. The study focuses on the effect of molecular weight of polymer melts on the material constants in the constitutive equations.

• Geomechanics and Engineering
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• v.32 no.2
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• pp.233-244
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• 2023

With the increasing amount of resources required by the society development, mining operations go deeper, which raises the requirements of studying the effects of temperature on the physical and mechanical properties of coal and adjacent rock. For now, these effects are yet to be fully revealed. In this paper, a mechanical-electromagnetic radiation (EMR) test system was established to understand the mechanical deterioration characteristics of coal by the effect of thermal treatment and its deformation and fracture characteristics under thermo-mechanical coupling conditions. The mechanical properties of high-temperature-treated coal were analyzed and recorded, based on which, reasons of coal mechanical deterioration as well as the damage parameters were obtained. Changes of the EMR time series under unconstrained conditions were further analyzed before characteristics of EMR signals under different damage conditions were obtained. The evolution process of thermal damage and deformation of coal was then analyzed through the frequency spectrum of EMR. In the end, based on the time-frequency variation characteristics of EMR, a method of determining combustion zones within the underground gasification area and combustion zones' stability level was proposed.