• Journal of Biomedical Engineering Research
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• v.20 no.1
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• pp.107-113
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• 1999

The purpose of this study was to develop a miniature imaging gamma probe with high performance that can detect small or residual tumors after surgery. Gamma probe detector system consists of NaI(Tl) scintillator, position sensitive photomultiplier tube (PSPMT), and collimator. PSPMT was optically coupled with 6.5 mm thick, 7.62 cm diameter of NaI(Tl) crystal and supplied with -1000V for high voltage. Parallel hexagonal hole collimator was manufactured for characteristics of 40-mm hole length, 1.3-mm hole diameter, and 0.22 mm septal thickness. Electronics consist of position and trigger signal readout systems. Position signals were obtained with summing, subtracting, and dividing circuit using preamplifer and amplifier. Trigger signals were obtained using summing amplifier, constant fraction discriminator, and gate and delay generator module with preamplifer. Data acquisition and processing were performed by Gamma-PF interface board inserted into pentium PC and PIP software. For imaging studies, flood and slit mask images were acquired using a point source. Two hole phantom images were also acquired with collimator. Intrinsic and system spatial resolutions were measured as 3.97 mm and 5.97 mm, respectively. In conclusion, Miniature gamma probe images based on the PSPMT showed good image quality, we conclude that the miniature imaging gamma probe was successfully developed and good image data were obtained. However, further studies will be required to optimize imaging characteristics.

• Archives of Plastic Surgery
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• v.37 no.6
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• pp.823-826
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• 2010

Purpose: Meningomyelocele is the most common type of neural tube defect disease. Early surgical treatment is recommended to prevent central nervous system infection. Several reconstruction methods were reported previously regarding surgical wound defect closure following meningomyelocele excision. In this article, we report two successful patients using the bilateral fasciocutaneous sliding V-Y advancement flap as a covering for meningomyelocele defects. Methods: Two patients with meningomyelocele were evaluated. Both patients were male and received their operations on the 1st and 4th day of life. After neurosurgeons completed their part of the operation, the V-Y advancement flap was used to close the defect. Initially a bilateral V-shape incision design was made on the skin such that the base of the V-flap measures identical to the size of the wound defect. An incision was made down to the fascia in order to allow the V-flaps to slide into the defect. Subfascial dissection was performed up to 1/3 to 1/4 the length of the V-flap from the wound while minimizing injury to the perforating vessels. Results: Both patients were treated successfully and there was no evidence of complication in 2 months follow up. Conclusion: Several reconstruction methods such as local flaps, skin graft and myocutaneous flaps were reported regarding meningomyelocele surgical wound defect closure. Bilateral fasciocutaneous sliding V-Y advancement flap is an easy method without involving the underlying muscles or a secondary skin graft in a short operation time. Therefore we recommend this treatment option for reconstruction of the wound defect following meningomyelocele excision.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.1-11
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• 2016

The effect of the migration of nanoparticles near the wall of a channel on the convective heat transfer in a laminar flow of $SiO_2$ nanoparticle suspensions (nanofluids) under constant wall heat flux boundary conditions was numerically and experimentally investigated in this study. The dynamic thermal conductivity of the aqueous $SiO_2$ nanofluids was measured using T-type thermocouples attached to the outer surface of a stainless steel circular tube (with a length of 1 m and diameter of 1.75 mm). The nanofluids used in this study were synthesized by dispersing $SiO_2$ spherical nanoparticles with a diameter of 24 nm in de-ionized water (DIW). The enhancement of the thermal conductivity of the nanofluids (e.g., an increase of up to 7.9 %) was demonstrated by comparing the temperature profiles in the flow of the nanofluids with that in the flow of the basefluids (i.e., DIW). However, this trend was not demonstrated in the computational analysis, because the numerical models were based on continuum assumptions and flow features involving nanoparticles in a stable colloidal solution. Thus, to explore the non-continuum effects, such as the modification of the morphology caused by nanoparticle-wall interactions on the heat exchanging surfaces (e.g., the isolated and dispersed precipitation of the nanoparticles), additional experiments were performed using DIW right after the measurements using the nanofluids.

• Journal of Korean Society of Forest Science
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• v.7 no.1
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• pp.19-27
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• 1968

As a preliminary investigation to obtain useful auto- and allopolyploids a ten year old tetraploid of Pinus densiflora induced from the colchicine treated seed was observed on the cytological, morphological and physioa logical characters in the present study and the results can be summarized as follows. 1. The number of chromosome at the base of needle was 48 so that it was recognized as a tetraploid. 2. The needles were thicker and the number of them on an individual was less than the 2n plant. The needle combined to a single was appeared 2%. 3. No difference was found in the number of stomata rows on the central part of needle between the tetraploid and 2n plant, however, guard cells of tetraploid increased 36% in the long diameter compared with 2n plant. 4. Microsporangiate storbile developed normally showing the same size with 2n plant while the size of pollen grain increased about 20% larger than 2n plant. 5. Germination percentage in vitro increased until 17 hours but decreased after 26 hours compared with 2n plant. The longest length of pollen tube during the germination period appeared in the tetraploid pollen.

• The Korean Journal of Zoology
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• v.27 no.1
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• pp.13-24
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• 1984

The fertilized eggs of Rana dybowskii were irradiated with UV (254 nm wave length) on the vegetal hemisphere to investigate the effects on the primordial germ cells (PGCs) and axis formation. The investigations were carried out in two ways; namely time course and UV dose. Up to 1,600 $ergs/mm^2$ of UV dose, irradiated at 60 min. after fertilization, there was no effect on the PGC number. However, the number of PGC comparing with that of unirradiated control was decreased more than 40%. As the amount of irradiation was increased, the number of PGC was inversely declined. The maximal dose of irradiation which eliminates PGC completely without inducing any axis abnormality was 4,800 $ergs/mm^2$. If the eggs were irradiated earlier with this amount the severer effect could be obtained. Thus the UV effect on the PGC number was most effective when irradiated by 60 min. post fertilization. Thereasfter stage. At UV doses over 9,600 $erge/mm^2$ other effects start to appear; namely abnormalities of nerual tube and axis formation. Therefore, comparative study on the UV sensitivity of PGC and axis formation was carried out. It was revealed that UV effect on the axis was drastically decreased at the time of $0.7\\sim0.8$ between fertilization and 1st cleavage, while the germ plasm was sensitive to UV until 4 cell stage.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.117-125
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• 2011

River bed variation drops storage capacity of dams and reservoirs, and furthermore deteriorates safety of banks and peers. Therefore, understanding of bed variation is important to use and manage river water. Study section is downstream part of Ji- Cheon nearby Ji-Cheon Bridge which is located in Gum river basin. The river surveying at fourteen places with the length of 1,320m were undertaken on November 7, 2003 and September 24, 2004, and the results of river surveying were analyzed for the study. Real bed variation was compared with the simulation results of HEC-6 and GSTARS 3.0. Cross section data for the simulation of HEC-6 and GSTARS3.0 were composed of the basis of river surveying data on November 7, 2003. Hydrological data were acquired from Gu-Ryong watermark located at Ji-Chun Bridge. The research results revealed that when using Toffaleti equation, simulation results of two models were similar to the real bed variation. The bed variation simulated by using GSRARS 3.0 with only one stream tube was similar to the real bed variation. The bed variation simulated by using two models(HEC-6 and GSTRARS 3.0) with Toffaleti equation was also similar to the real bed variation. Therefore, it is expected that HEC-6 and GSTARS 3.0 models have applicability to predict the bed variation at the downstream of Ji-Cheon.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.686-693
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• 2018

Various types of re-bar splicing methods have been developed and applied to reinforced concrete (RC) structures in the field. According to previous studies, the coupler splice is relatively superior to the lap splice in terms of cost efficiency when the diameter or strength of the re-bar is larger or higher. This study was performed to develop a filler type mechanical splice for a high-strength re-bar (SD600) in reinforced concrete structures. The deformed re-bars were inserted into a circular steel tube coupler and high-strength epoxy filler was then injected into the coupler. The splice system was completed by hardened filler in a coupler. The epoxy filler was used as the manufactured production epoxy to conduct experiments of filler type mechanical splice specimens, and to observe the failure loads and failure aspects of the specimens. For this goal, the experiment of one-way tensile test was conducted for the epoxy filler type mechanical splices specimens according to the compressive strength of epoxy, length of coupler, and diameter of re-bar. The shape of failure of the re-bar coupler splice showed that the re-bars were pulled between the lugs of the re-bars as a result of the shear fracture of the hardened epoxy. The actual failure load of the experiment specimen was approximately 2 times higher than the expected failure load of the epoxy filler, which greatly improves the failure load of the hardening epoxy filler due to the restraint of the steel coupler.

• Journal of Broadcast Engineering
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• v.25 no.6
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• pp.861-869
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• 2020

We introduce the application that automatically makes several images stored in user's device into one video by using the different climax patterns appearing for each film genre. For the classification of the genre characteristics of movies, a climax pattern model style was created by analyzing the genre of domestic movie drama, action, horror and foreign movie drama, action, and horror. The climax pattern was characterized by the change in shot size, the length of the shot, and the frequency of insert use in a specific scene part of the movie, and the result was visualized. The model visualized by genre developed as a template using Firebase DB. Images stored in the user's device were selected and matched with the climax pattern model developed as a template for each genre. Although it is a short video, it is a feature of the proposed application that it can create an emotional story video that reflects the characteristics of the genre. Recently, platform operators such as YouTube and Naver are upgrading applications that automatically generate video using a picture or video taken by the user directly with a smartphone. However, applications that have genre characteristics like movies or include video-generation technology to show stories are still insufficient. It is predicted that the proposed automatic video editing has the potential to develop into a video editing application capable of transmitting emotions.

• Nuclear Engineering and Technology
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• v.27 no.6
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• pp.811-824
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• 1995

The CANDU element bowing is attributed to actions of both the thermally induced bending moments and the bending moment due to hydraulic drag and mechanical loads, where the bowing is defined as the lateral deflection of an element from the axial centerline. This paper consider only the thermally-induced bending moments which are generated both within the sheath and the fuel and sheath by an asymmetric temperature distribution with respect to the axis of an element The generalized and explicit analytical formula for the thermally-induced bending is presented in con-sideration of 1) bending of an empty tube treated by neglecting the fuel/sheath mechanical interaction and 2) fuel/sheath interaction due to the pellet and sheath temperature variations, where in each case the temperature asymmetries in sheath are modelled to be caused by the combined effects of (i) non-uniform coolant temperature due to imperfect coolant mixing, (ii) variable sheath/coolant heat transfer coefficient, (iii) asymmetric heat generation due to neutron flux gradients across an element and so as to inclusively cover the uniform temperature distributions within the fuel and sheath with respect to the axial centerline. As the results of the sensitivity calculations of the element bowing with the variations of the parameters in the formula, it is found that the element bowing is greatly affected relatively with the variations or changes of element length, sheath inside diameter, average coolant temperature and its variation factor, pellet/sheath mechanical interaction factor, neutron flux depression factor, pellet thermal expansion coefficient, pellet/sheath heat transfer coefficient in comparison with those of other parameters such as sheath thickness, film heat transfer coefficient, sheath thermal expansion coefficient and sheath and pellet thermal conductivities.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.361-365
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• 2023

On May 12, 2023, a juvenile specimen (37.6 mm in standard length) belonging to the order Aulopiformes was collected from southern Yokjido, Tongyeong, Korea, using a Bongo net. The specimen was identified as the member of the family Scopelarchidae in having a slender body, a large mouth, large tube-like eyes, a long anal fin base, a developed adipose fin and no photophores on body. Finally, we identify the specimen as Scopelarchoides danae Johnson, 1974 in having 8 dorsal fin rays, 20 pectoral fin rays, 9 pelvic fin rays, 26 anal fin rays, dorsal fin located anteriorly than pelvic fin, and two large pigments below the pectoral fin and posterior to the pelvic fin. Scopelarchoides danae is distinguished from Scopelarchoides signifer in having less dorsal fin rays (8 vs. 9~10) and pectoral fin rays (20 vs. 22~25). The species differs from Scopelarchus guentheri and Scopelarchus analis in that it has no stripes along the both upper and lower of lateral line, and from Scopelarchus michaelsarsi in that it has more anal fin rays (26 vs. 18~21). Because this is the first occurrence among Korean fish fauna, we present its detailed morphological traits, and its new Korean name as "Nun-bang-ul-mae-tung-i".