• The Journal of the Korean bone and joint tumor society
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• v.9 no.1
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• pp.31-37
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• 2003

Introduction: The purpose of this study is to assess the efficacy of calcium sulfate as a bone graft substitute in the treatment of benign bone tumor. Materials and Method: Between December 2000 and November 2001, 18 patients with a benign bone tumor were treated with crettage and the defects were filled with calcium sulfate (Osteoset$^{(R)}$:Wright Medical Co. USA) as a bone graft substitute. Average age was 28.4 years and mean follow up period was 12.3 months. Calcium sulfate mixed with autograft was used in 6 cases, calcium sulfate with allograft in 2 cases, and calcium sulfate alone was used in 10 cases. The degree of absorption of calcium sulfate and new bone formation at plain radiograph was analyzed at immediate postoperative and postoperative 3 months and 6 months follow up. Results: At 3 months postoperatively, 92% of calcium sulfate was absorbed, and at 6 months postoperatively, 89% of new bone formation was observed. There was no difference in the resorption and new bone formation between the group using bone graft and the group osteoset$^{(R)}$ alone, different preoperative diagnosis and even different locations. There was no complication. Conclusion: Calcium sulfate(Osteoset$^{(R)}$) is a safe and effective bone graft substitute in the treatment of benign bone tumors, especially for the children in whom autograft is not recommandable.

• Archives of design research
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• v.15 no.4
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• pp.177-188
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• 2002

A thousands of chairs have designed from the Victorian era to the present. Thonet's Nol4 chair in 1859, Wright's high-back chair in 1904, Ritveld's red/blue chair in 1917, Breuer's Wassily chair in 1925, Aalto's Paimio chair in 1932, Eames's DAR chair in 1948, Piero Gatti's Sacco chair in 1969, Starck's Von Volgelsang chair in 1984, Stumpf's Aeron Chair in 1992, Little's 'Coat of arms' chair in 1994 - the list of architects who have seized the opportunity to express their theories in the design of a chair is seemingly endless. Architects such as Machintosh(1868-1928), Wright(1807-1959), Aalto(1898-1976) included chairs within their artistic schemes for interiors and buildings. But as the manufacture of chairs moved away from the domain of the craftsman towards that of the industrial process, architects were also ideally positioned, with their background knowledge of engineering, to pioneer innovative chair design within the constraints of modern manufacturing technology. Beyond matters of function and structure, the fundamental worth of chairs, past or present, lies in their communication of attitudes, ideas and values. The persuasiveness of a chair depend on the clarity of its rhetoric. Chair has become an ideal medium for designers to make their visual statements and construct their individual manifestos. In chair design there is a ping-pong game played out between absurd and useful design, and this game is one way in which the design profession explores itself.

• Journal of the Korean earth science society
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• v.41 no.3
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• pp.291-306
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• 2020

In this study, we developed a learning progression for the structure of the solar system using multi-tier supply form items and validated its appropriateness. To this end, by applying Wilson's (2005) construct modeling approach, we set up 'solar system components,' 'size and distance pattern of solar system planets,' and 'solar system modeling' as the progress variables of the learning progression and constructed multi-tier supply form items for each of these variables. The items were applied to 150 fifth graders before and after the classes that dealt with the 'solar system and star' unit. To describe the results of the assessment, the students' responses to each item were categorized into five levels. By analyzing the Wright map that was created by applying the partial credit Rasch model, we validated the appropriateness of the learning progression based on the students' responses. In addition, the validity of the hypothetical pathway that was established in the learning progression was verified by tracking changes in the developmental level of students before and after the classes. The results of the research are as follows. The bottom-up research method that used multi-tier supply form items was able to elaborately set the empirical learning progression for the conceptualization of the structure of the solar system that is taught in elementary school. In addition, the validity of the learning progression was high, and the development of students was found to change with the learning progression.

• Journal of The Korean Association For Science Education
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• v.36 no.6
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• pp.815-833
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• 2016

This study investigated children's (grade 3 to 9) responses to assessment items on energy as a cross-cutting concept in order to get basic information for a learning progression. The assessment consisted of 8 ordered multiple-choice items at the contexts of electric circuit, mechanical energy of falling objects, phase change of matter, dissolution, biological phenomena of a lizard, food chain, radiative equilibrium between Sun and Earth, and the system of water cycling. Children's responses to each item were analyzed with using cross-tabulations in terms of grades and item option levels and Wright map and Differential item functioning based on Rasch modeled item response analysis. The results offered empirical evidence of children's development of understanding energy from relation between energy and its phenomena, types of energy, transfer and conversion of energy, towards conservation and equilibrium of energy for all of eight contexts. Children of each grade did not fully understand energy conservation. As grade goes up, their understandings of energy transfer and conversion were differentiated across the contexts and topics of energy. According to Rasch analysis, children had easier understanding of energy on dissolution and poorer understanding of energy on water cycling than that on other contexts. It was discussed and suggested that the results of this study help us organize science topics with regard to energy when developing new national science curriculum.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.296-296
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• 2014

We investigate experimentally and theoretically the splitting of surface plasmon (SP) resonance peaks under TE- and TM-polarized illumination. The SP structure at infrared wavelength is fabricated with a 2-dimensional square periodic array of circular holes penetrating through Au (gold) film. In brief, the processing steps to fabricate the SP structure are as follows. (i) A standard optical lithography was performed to produce to a periodic array of photoresist (PR) circular cylinders. (ii) After the PR pattern, e-beam evaporation was used to deposit a 50-nm thick layer of Au. (iii) A lift-off processing with acetone to remove the PR layer, leading to final structure (pitch, $p=2.2{\mu}m$; aperture size, $d=1.1{\mu}m$) as shown in Fig. 1(a). The transmission is measured using a Nicolet Fourier-transform infrared spectroscopy (FTIR) at the incident angle from $0^{\circ}$ to $36^{\circ}$ with a step of $4^{\circ}$ both in TE and TM polarization. Measured first and second order SP resonances at interface between Au and GaAs exhibit the splitting into two branches under TM-polarized light as shown in Fig. 1(b). However, as the incidence angle under TE polarization is increased, the $1^{st}$ order SP resonance peak blue-shifts slightly while the splitting of $2^{nd}$ order SP resonance peak tends to be larger (not shown here). For the purpose of understanding our experimental results qualitatively, SP resonance peak wavelengths can be calculated from momentum matching condition (black circle depicted in Fig. 2(b)), $k_{sp}=k_{\parallel}{\pm}iG_x{\pm}jG_y$, where $k_{sp}$ is the SP wavevector, $k_{\parallel}$ is the in-plane component of incident light wavevector, i and j are SP coupling order, and G is the grating momentum wavevector. Moreover, for better understanding we performed 3D full field electromagnetic simulations of SP structure using a finite integration technique (CST Microwave Studio). Fig. 1(b) shows an excellent agreement between the experimental, calculated and CST-simulated splitting of SP resonance peaks with various incidence angles under TM-polarized illumination (TE results are not shown here). The simulated z-component electric field (Ez) distribution at incident angle, $4^{\circ}$ and $16^{\circ}$ under TM polarization and at the corresponding SP resonance wavelength is shown in Fig. 1(c). The analysis and comparison of theoretical results with experiment indicates a good agreement of the splitting behavior of the surface plasmon resonance modes at oblique incidence both in TE and TM polarization.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.4
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• pp.255-267
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• 2020

Under SLD conditions, due to the large size of droplets, physical phenomena such as wall-droplet interaction and deformation have a significant effect on the icing process. Accordingly, many studies have been conducted in order to computationally simulate SLD effects. As one of the efforts, post-processing method have been proposed to describe wall-droplet interaction effect, which modified collection efficiency using Wright model. However, since the model doesn't properly consider the wall condition, it still overestimated collection efficiency and impingement limit. To solve this problem, impingement areas were divided into 3 different regions, and the post-processing method was introduced with the new wall-droplet interaction model developed based on Bai and Gosman rebound model. In order to consider the effect of deformation, the most suitable model was selected by comparing the deformation models used in the various icing codes. As a result, the modified post-processing method showed improved accuracy in predicting the impingement limits and collection efficiency by further estimating mass flux loss due to rebound, and it was observed that the result was the closest to the experimental data when the deformation effect was included by using Wiegand model.

• Science of Emotion and Sensibility
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• v.15 no.1
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• pp.37-46
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• 2012

We tested the effects of endogenous attention and reorienting on the performance of detection task. In the classic detection paradigm of Posner and Cohen (1980), performance on target detection is measured, where target appears either on the same or difference spatial location of cue stimulus after brief period of SOA (stimulus onset asynchrony). In this study, we induced exogenous attention by manipulating predictability of cue for target, and also induced reorientation by inserting additional (reorienting) cue between initial cue and target. Experiment 1 had three conditions of reorienting speed: Early, middle, and late. Facilitation and IOR (inhibition of return) occurred in different forms depending on SOA and reorienting speed, but we were not able to discover interpretable pattern in the results. However, reanalysis of early reorienting condition revealed that facilitation and IOR occurred in a crossed manner where short SOA found facilitation and long SOA did IOR, the typical results of simple detection task. Experiment 2 collected additional data to replicate the results in early reorienting condition of experiment 1. The results obtained that facilitation occurred with short SOA and IOR with long SOA. These results contrast with those of Wright and Richard (2000) where they reported elimination of IOR when cue had predictability of target locations. These results suggest that additional cue (here, orienting cue), which rapidly appears before extinction of IOR by prior cue, brings about double IOR. The present research demonstrates that even when attention is allocated to certain location via endogenous mechanism, rapidly repeating cues in certain location maximizes IOR that offsets the effects of endogenous attention to the same location.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.30-36
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• 2001

Schisandra nigra Max. has been cultivated far a medical use as well as food. It is an endemic species which has a unique habitat at the altitude of 600-1,400 m in Cheju island. In this study, three natural populations of S. nigra were investigated by using of starch-gel electrophoresis to determine the extent and distribution of genetic diversity. Except 2 monomorphic locus (Mdh-2 and Pgi-1), 4 of the 6 isozyme locus (Idh, Mdh-2, Mnr, and Pgi-2), verified from 4 isozymes, revealed polymorphism in the three populations of S. nigra. The mean number of allele per locus was 1.7 and the percentages of polymorphism loci were 38.9% at 95% level and 50% at 99% level respectively. The observed and estimated heterozygosities were 0.141 and 0.147 respectively. Although plants which were in the face of crisis and distributed in the restricted area, have been known to the very low degree of genetic variation, S. nigra showed higher genetic variation than others. Genetic variation was mostly allocated within population and individuals than that among populations. The result of Wright's F analysis estimates of $F_{IT}$ and $F_{IT}$ showed that S. nigra population revealed Hardy-Weinberg steady state.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.2
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• pp.118-122
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• 2000

A comlementary call line CR2 is curretly used to propagte the Disabled Infectious Single Cycle Herpes Simplex Virus Typee2 (DISC HSV-2) on a small Iaboratory scale upto 15 L. These cultures are initiated by passaging the cells from roller bottle cultures. Whilst this is suitable for the laboratory scale it is totally impractical for use in seeding an industrial manufacturing scaled version of the culture. It is paramount to have a robust system for passaging cells from a small microcarrierier culture system to a larger one by a serial subculturing regime. Here we report on the successes we have had in our laboratory in scaling up out production system for the DISC HSV-2 from small 1-L cultures to a 50-L vessel with the maintenance of the viral productivity. Ease of use, reproducibility and the need to minimise overall production time were factors which were taken into consideration whils developing our procedures. We were aware of the need to keep a production train simple and as short as possible as this was the amall scale study for an envisaged manufacturing process.

• Journal of Information Technology Services
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• v.14 no.1
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• pp.99-113
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• 2015

Adaptive bitrate (ABR) streaming technology has become an important and prevalent feature in many multimedia delivery systems, with content providers such as Netflix and Amazon using ABR streaming to increase bandwidth efficiency and provide the maximum user experience when channel conditions are not ideal. Where such systems could see improvement is in the delivery of live video with a closed loop cognitive control of video encoding. In this paper, we present streaming camera system which provides spatially and temporally adaptive video streams, learning the user's preferences in order to make intelligent scaling decisions. The system employs a hardware based H.264/AVC encoder for video compression. The encoding parameters can be configured by the user or by the cognitive system on behalf of the user when the bandwidth changes. A cognitive video client developed in this study learns the user's preferences (i.e. video size over frame rate) over time and intelligently adapts encoding parameters when the channel conditions change. It has been demonstrated that the cognitive decision system developed has the ability to control video bandwidth by altering the spatial and temporal resolution, as well as the ability to make scaling decisions