• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.8
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• pp.563-569
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• 2008

Radiative, heating is suitable for outdoor heating system in windy and cold seasons. Optimal design of the reflector is very important to maximize heat transfer to a specific target area in the open space. The geometrical optical theory can be applied to analyze efficiency of the reflector. Commercial ray tracing computer programs are available only for limited geometries of the reflector. Alternatively, it may be designed and analyzed through an approximated simple lens theory. Two types of reflectors are analyzed using either of these methods. The key issue in this paper is to propose a new illumination experimental method for determination of the radiative efficiency. Optical light source and illuminometer are employed. The calculated efficiency of the reflector is compared with experimental one for checking the reliability. The relative errors between the experimental and analytical results are less than 5%, which proves the validity of this method. Based on these methodologies, a practical reflector and heating lamp unit is developed.

• Smart Structures and Systems
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• v.32 no.2
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• pp.123-133
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• 2023

This paper proposes a thermography-based coating thickness estimation method for steel structures using model-agnostic meta-learning. In the proposed method, a halogen lamp generates heat energy on the coating surface of a steel structure, and the resulting heat responses are measured using an infrared (IR) camera. The measured heat responses are then analyzed using model-agnostic meta-learning to estimate the coating thickness, which is visualized throughout the inspection surface of the steel structure. Current coating thickness estimation methods rely on point measurement and their inspection area is limited to a single point, whereas the proposed method can inspect a larger area with higher accuracy. In contrast to previous ANN-based methods, which require a large amount of data for training and validation, the proposed method can estimate the coating thickness using only 10- pixel points for each material. In addition, the proposed model has broader applicability than previous methods, allowing it to be applied to various materials after meta-training. The performance of the proposed method was validated using laboratory-scale and field tests with different coating materials; the results demonstrated that the error of the proposed method was less than 5% when estimating coating thicknesses ranging from 40 to 500 ㎛.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.3
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• pp.25-34
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• 2018

This paper presents a heating source of carbon nanofibers for the efficiency and the drying performance of laundry dryer, and focuses on the applicability-evaluation of its source. To design the proposed heating module, experiments were conducted in terms of surface temperature and surface temperature distribution characteristics of carbon nanofiber lamps. The surface temperature of the lamps increased linearly with increment of a current to flow a lamp and revealing the increasing pattern as the length of the ramps is shorter. The proposed heating source was evaluated based on drying efficiency, moisture evaporation rate at laundry, and internal temperature of a drum during drying process. The drying efficiency satisfied a 45% which is specified in KS C 9319. The moisture evaporation rate and the internal temperature of the drum were respectively 98.88% and $61.1^{\circ}C$, which are similar to that of S's company dryer. From the evaluation and actual drying test results, the proposed carbon nanofiber lamp heating module is considered to be applicable as a heat source for laundry dryer in terms of drying efficiency and drying performance. it is possible to obtain a heat source at a high temperature, an excellent calorific value, an improvement in drying performance, and an effect of sterilizing laundry due to the emission of far-infrared rays. In addition to the applicability, the difference of the drying efficiency between the dryers was analyzed in detail based on the power consumption of the heat sources.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.203-210
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• 2014

The purpose of this study was to investigate the effect of experimental warming using infrared lamps on seed germination and seedling survival rate of Pinus densiflora and Abies holophylla. The air temperature of warmed plots had been automatically maintained 3 higher than control plots. The percent germinations (%) of the two coniferous species were higher in warmed plots than in control plots, however a significant difference appeared only in A. holophylla. In addition, P. densiflora and A. holophylla showed the shorter mean germination time (days), higher germination rate ($seed{\cdot}day^{-1}$) and germination energy (%) in warmed plots than in control plots. A. holophylla showed a higher seedling mortality rate in the warmed plots than in control plots because of increased air and soil temperatures and decreased soil moisture. However, seedling survival rate of P. densiflora showed no significant difference by experimental warming. In the future, changed air and soil temperatures and soil moisture due to global warming will induce a variety of changes in seed germination and survival rate of tree species in nursery culture. Therefore, it is necessary to establish adaptation strategies that improve techniques in nursery culture against global warming.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.217-223
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• 2021

5-aminolevulinic acid (ALA) is a representative photosensitizer used in numerous fields including cancer diagnosis and treatment. In this study, experiments were conducted to optimize the growth of Rhodobacter sphaeroides and production of ALA through LED irradiation of various wavelengths, addition of organic acid precursors of ALA, and changes in glucose concentration. After 72 h cultivation, the 850 nm wavelength LED irradiated at the same light intensity as the incandescent lamp increased the growth of R. sphaeroides and the production of ALA about 1.5- and 1.8-fold as compared with the control, respectively (p <0.0001 and p <0.0001). As a result of culturing R. sphaeroides by irradiating an LED with a wavelength of 850 nm after adding organic acid to the final concentration of 5 mM in culture medium, the production of ALA was increased about 2.8-fold in medium supplemented with pyruvic acid compared with the control (p <0.0001). In addition, the growth of the strain and the production of ALA were increased about 2.9- and 3.4-fold in medium supplemented with 40 mM glucose compared to the control which added only 5 mM pyruvic acid, respectively (p <0.0001 and p <0.0001). The yield of ALA per cell dry mass was about 1.4 folds higher than that of the control in 20 and 40 mM glucose, respectively (p <0.001). In conclusion, the growth of R. sphaeroides and production of ALA were increased by 850 nm wavelength LED irradiation. It also optimized the growth of R. sphaeroides and production of ALA through organic acid addition and glucose concentration changes.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.5 no.2
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• pp.1-9
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• 2007

Purpose: The purpose of this study was to investigate influence of superficial heat and deep heat for lumbo-sacral segment on H-reflex. Methods: Subjects of this research were 12 normal men and women (6 men and 6 women) and they were assigned to superficial heat group (6) and deep heat group (6). Heat treatment was applied between Th12-L2 by placing them at prone posture. superficial heat was applied for 20 min at 30 cm height with infrared lamp. Deep heat was applied for 20 mm at 5 cm height with 100 watt of microwave diathermy. H-reflex used diagnostic electromyography, active electrode was placed at muscle belly of medial gastrocnemius muscle at prone posture and electrical stimulation was given to posterior tibial nerve. Measurement was made before and after experiment and 10 min. and 20 min. after experiment. All data were analyzed with window 12.0 program, comparison of differences among measured items of groups according to repeated measurement was made with repeated measures ANOVA and significance level a was 0.05. Results: M latency at latency analysis showed little changes at two groups. H latency was reduced a little immediately after experiment and recovered to original state, there was significant difference. In analysis of amplitude, Mmax amplitude showed rise a little immediately after.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.4
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• pp.15-24
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• 2014

Recently, a variety of printing technologies, including ink jet, gravure, and roll-to-roll (R2R) printing, has generated intensive interest in the application of flexible and wearable electronic devices. However, the actual use of printing technique is much limited because the sintering process of the printed nanoparticle inks remains as a huge practical drawback. In the fabrication of the conductive metal film, a post-sintering process is required to achieve high conductivity of the printed film. The conventional thermal sintering takes considerable sintering times, and requires high temperatures. For application to flexible devices, the sintering temperature should be as low as possible to minimize the damage of polymer substrate. Several alternative sintering methods were suggested, such as laser, halogen lamp, infrared, plasma, ohmic, microwave, and etc. Eventually, the new sintering technique should be applicable to large area, R2R, and polymer substrate as well as low cost. This article reviews progress in recent technologies for several sintering methods. The advantages and disadvantages of each technology will be reviewed. Several issues for the application in R2R process are discussed.

• Journal of Acupuncture Research
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• v.23 no.1
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• pp.95-103
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• 2006

Objectives : This study was to evaluate the clinical effectiveness of Bee Venom acupuncture therapy for acute ankle sprain. Methods : From September 1st, 2005 to December 31st, 2005, the 60 patients who had visited Conmaul oriental medical hospital with acute ankle sprain were sample into 2 groups for this study; one group for the bee-venom acupuncture therapy combined with needle acupuncture therapy and the other group for needle acupuncture therapy only at least 3 times respectively. Both group had been treated with same additional infrared lamp, physical therapy and ankle supporter during the whole treatment period. Among 60 patients, 20 participants satisfied the whole inclusion criteria. To estimate the efficacy of treatments, Numerical Rating System(NRS) and Ankle-Hindfoot Scale(AHS) were applied before 1st and 4th treatment. Each score results were analysed and compared by Mann-Whitney test and Wilcoxon signed rank test with the level of 5% significance. Result : The NRS score in bee-venom acupuncture therapy group was increased significantly and the AHS score in bee-venom therapy group was decreased significantly compared to each of single acupuncture therapy group(P<0.01). The score change comparisons between the two groups had no significance before and after the treatment. Conclusion : Both bee-venom acupuncture therapy and single acupuncture therapy were effective to treat the acute ankle sprain. but there were no significant data to prove that bee-venom acupuncture therapy is more effective than single acupuncture therapy.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.2
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• pp.187-192
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• 2013

Fatigue crack was detected from a temperature change around surface crack using the thermographic technique. Thermal gradient across the crack decreased very much due to thermal resistance of contact surface in the crack. Heat diffusion flow passing through the discontinuity was visualized in temperature by infrared camera to find and locate the crack. A fatigue crack specimen(SM-45C), which was prepared according to KS specification and notched in its center to initiate fatigue crack from the notch tip, was heated by halogen lamp at the end of one side to generate a heat diffusion flow in lateral direction. A abrupt jump in temperature across the fatigue crack was observed in thermographic image, by which the crack could be located and sized from temperature distribution.

• The Journal of the Korean dental association
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• v.48 no.12
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• pp.893-918
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• 2010

This article is purposed of reviewing the development history of Japanese dental devices and instrument, and their related advertisement activities during the Japanese colonized period in Korea in early 20th century. Japanese dental devices and instrument were redesigned to accommodate their ergonomic shape above the simple imitation, and it implies the excessive desires brought them frustrations. The tragic earthquake on Sep. l, 1923, medical insurance law enforcement on Jan. 1, 1927, celebration of "Cavity prevention Day" started on Jun. 4, 1928, and the attack of Manchuria and China by Japan after 1931, all of these historical incidents become the preliminary requirement for the development of dental devices. On Nov. 1, 1937, Japanese government started to control dental materials, driving the campaigns for excluding foreign products and encourging the use of local products. In 1939, Nakajima dental manufacturers used this political and social atmosphere on their advertisement as saying "Our Nakajima's products have no compromise with the short raw materials, but only commitment to our quality". Since after 1940, the price and supply have been strongly under control, and the control group was appeared to manage all of supply and distribution of raw materials, regular price system, and specifications. At last, the Japanese national power were devastated in its production and distribution capacities, and get to the frustrated period. The main advertised dental devices and instruments in Korea during the Japanese colonized period were 1) dental chair, unit and cabinet, 2) dental x-ray, 3) compressors, 4) dental needles, 5) small instrument and carryon medical(emergency) kit, 6) oral hygiene and pyorrhea alveolaris, infrared rays, sunlight lamp, ultrashort wave treatment devices, 7)crown former, electric furnace, casting machine, articulator, electric lathe, and laboratory equipments, etc.