• KSBB Journal
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• v.14 no.6
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• pp.742-746
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• 1999

The microalgal, Chlorella sp. HA-1, had good $CO_2$ fixation efficiency compared to other algal strains at the same operating condition. In this study, Chorella sp. HA-1 showed similar tolerance both 10% and 20% $CO_2$ concentration. By optimization of the major operation variables such as pH, initial cell concentration, light intensity, the $CO_2$ fixation rate could be raised to a reasonably high value, 372 $gCO_2/m^2{\cdot}day$ in a 3 L internally illuminated photobioreactor. In order to maintain the $CO_2$ fixation rate for a long time, the method of semi-continuous operation was employed, in which dilution ratio was the controlling parameter. Starting with the dilution ratio of 0.5 with the increased increment of 0.1, the constant $CO_2$ fixation rate was obtained.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.293-297
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• 2003

A series of laboratory experiments was conducted to investigate the fixation characteristics of poly(vinylalcohol)-poly(methacrylic acid)(PVA-PMAA) mixed solution on the soluble (equation omitted)-radionuclides. Using the potentiometric titration technique, it was found out that the PVA and PMAA in a solution form intermacromolecular complex. The mobilized portion of each radionuclide by water from sand surface treated with a fixative was measured by ${\gamma}$-ray spectroscopy, The mobilized portion of minor radionuclides such as $^{241}$ Am, $^{154}$ Eu, $^{155}$ Eu and $^{144}$ Ce were higher than those of $^{134}$ Cs and $^{137}$ Cs. The capability of PVA-PMAA system was better among the candidate solutions for the fixation of total (equation omitted)-radioactivity, $^{134,137}$Cs which is composed of more than 85 % of total ${\gamma}$-radioactivity could be fixed effectively by the PVA-PMAA solution.

• Korean Institute of Interior Design Journal
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• v.24 no.2
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• pp.125-133
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• 2015

Gaze induction characteristics in space vary depending on characteristics of spatial components and display. This study analyzed dominant eye-fixation characteristics of three zones of department store space. Eye-fixation characteristics depending on spatial components and positional relationship can be defined as follows. First, [**.jpg] was used as an extension in the process of storing the image photographed during image data processing for analysis in pixels and due to compressed storage of image data, the image produced with a clear boundary was stored in neutral colors. To remove this problem, the image used in operation was re-processed in black and white and stored in the [**.bmp] format with large capability, at the same time. As the result, the effort caused by unnecessary colors in the program operation process was corrected. Second, the gaze ratio to space area can be indicated as a strength of each gaze zone and when analyzing the gaze strength of the three zones, the left store was a zone with a "little strong" gaze strength of "102.8", the middle space was a zone with an "extremely weak" gaze strength of "89.6" and the right store was a zone with an "extremely strong" gaze strength of "117.2". Third, the IV section had a strong strength of gaze on the middle space and the right store and the V section showed a markedly strong strength of gaze on the left and right stores. This tendency was the same as the VI section with the strongest gaze strength and the right store had a little strong gaze strength than the left store.

• Journal of Plant Biology
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• v.30 no.3
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• pp.205-213
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• 1987

Soybean, inoculated with effective Rhizobium japonicum 110, were grown by sand culture with nutrient solution containing either of 0, 1, 3, 10 or 30mM NO3-/l, and analyzed growth characteristics, NR activity, N2-fixation activity, and changes of ureide contents during the growing period. The amount of nodule formation decreased abruptly by nitrate treatment, the maximum nodule dry weight was 1.59, 1.05, 0.78, 0.09 and 0.008 g plant-1, respectively for each treatment on the 98th day. Specfic activity of N2-fixation showed the maximum rates of 140, 101, 37, 5 and 2.2 nM dw.mg-1.hr-1, respectively for each treatment in the earlier growth period. The maximum acetylene reduction activity on the 98th day after sowing was 81.5, 35.3, 14.3, 0.1 and 0.0045 $\mu$M C2H4 plant-1.hr-1, respectively for 0, 1, 3, 10 and 30 mM of NO3- gradients. Nitrate reduction activity increased along with nitrate gradients, and decreased abruptly with age. Relative abundance of ureides in plant organs was high in reproductive growth, and showed the maximum value in fully symbiotic dependent plant. Relative abundance of ureides in stem is a useful indication for the evaluation of nitrogen fixation in nodules of symbiotic plant.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.46 no.6
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• pp.393-402
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• 2020

Objectives: Here, we present cases of mandibular fracture that were managed with the cortical lag screw fixation technique (CLSFT) in order to critically evaluate technique indications and limitations of application at various fracture sites. Materials and Methods: This was a retrospective cohort study. The study sample was composed of patients suffering from mandibular fractures that were treated by the CLSFT. The outcome variables were fracture type, duration of surgery, number of screws, and pattern of application. Other study categories included patient demographics and causes of injury. Chi-square tests were used to assess descriptive and inferential statistical differences, and the P-value was set at 0.05. Results: Thirty-three patients were included in the study sample, with a mean age of 30.9±11.5 years and a male predominance of 81.8%. The technique was applied more frequently in the anterior mandibular region (51.5%) than in other sites. Double CLSFT screws were required at the symphysis and parasymphysis, while single screws were used for body and angle regions. No intraoperative and postoperative variables were significantly different except for surgical duration, which was significantly different between the sites studied (P=0.035). Conclusion: We found that CLSFT is a rapid, cost-effective technique for the fixation of mandibular fractures yielding good treatment results and very limited complications. However, this technique is sensitive and requires surgical expertise to be applied to mandibular fractures that have specialized characteristics.

• Applied Biological Chemistry
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• v.48 no.3
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• pp.189-200
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• 2005

Biological nitrogen fixation is an important process for academic and industrial aspects. This review will briefly compare industrial and biological nitrogen fixation and cover the characteristics of biological nitrogen fixation studied in Azotobacter vinelandii. Various organisms can carry out biological nitrogen fixation and recently the researches on the reaction mechanism were concentrated on the free-living microorganism, A. vinelandii. Nitrogen fixation, which transforms atmospheric $N_2$ into ammonia, is chemically a reduction reaction requiring electron donation. Nitrogenase, the biological nitrgen fixer, accepts electrons from biological electron donors, and transfers them to the active site, FeMo-cofactor, through $Fe_4S_4$ cluster in Fe protein and P-cluster in MoFe protein. The electron transport and the proton transport are very important processes in the nitrogenase catalysis to understand its reaction mechanism, and the interactions between FeMo-cofactor and nitrogen molecule are at the center of biological nitrogen fixation mechanism. Spectroscopic studies including protein X-ray crystallography, EPR and $M{\ddot{o}}ssbauer$, biochemical approaches including substrate and inhibitor interactions as well as site-directed mutation study, and chemical approach to synthesize the FeMo-cofactor model compounds were used for biological nitrogen fixation study. Recent research results from these area were presented, and finally, a new nitrogenase reaction mechanism will be proposed based on the various research results.

• Journal of Science Education
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• v.34 no.2
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• pp.203-210
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• 2010

The characteristics of diffraction gratings, fabricated using Slavich PFG-01 plates as a holographic recording material, were investigated using various bleach techniques. The changes in diffraction efficiencies, under given development conditions, resulting from the use of a new reversal bleach and a new fixation free rehalogenating bleach are investigated. From the experimental results, it was found that the diffraction efficiencies are influenced by the composition of the developer, the reversal bleach and the fixation free rehalogenating bleach. In this study, the highest values of the maximum diffraction efficiency was obtained when PFG-01 plates were developed in AAC developers contained with l-ascorbic acid 20 g/L and sodium carbonate 60 g/L, processed by a reversal bleach, as high as 89.0%. Moreover, the maximum diffraction efficiency of 82.1% was obtained when PFG-01 plates were processed by a fixation free rehalogenating bleach. In addition, higher diffraction efficiencies are yielded in the case of the revesal bleach than in the case of the fixation free rehalogenating bleach.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.725-728
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• 2006

This research investigates the characteristics of chloride fixation in non-sintering cement(NSC) matrix. NSC was manufactured by adding phosphogypsum and slack lime to granulated blast furnace slag as sulfate and alkali activators. As a result, the concentration of chloride ion in pore solution of NSC-solidified matrix is more low than that of OPC-solidified matrix containing the same chloride content in cement paste. Also, the concentration of chloride ion in pore solution of NSC-solidified matrix is similar with that of BSC-solidified matrix containing the same chloride content in cement paste.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1271-1277
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• 2001

Objectives : Since vertebroplasty has been introduced, we performed short segment pedicle screw fixation with augmented intra-operative vertebroplasty in patients with unstable thoraco-lumbar fracture. Our intentions are to demonstrate the efficacy and indication of this new technique compare to conventional methods. Material and Methods : The surgery comprised of pedicle screw fixations on one level above and below the fracture site, and the fractured level itself, if pedicle is intact, and intra-operative vertebroplasty under the fluoroscopic guide with in-situ postero-lateral bone graft. Also, in cases of bone apposition, we removed those with small impactor through a transfascetal route. During the last 2 years, we performed in seven(7) unstable thoraco-lumbar fracture patients who consisted of two different characteristics, those four(4) with primary or secondary osteoporosis and three(3) of young and very healthy. All patients were followed clinically by A.S.I.A. score and radiography. Results : Mean follow up period was 14 months. We observed well decompressed state via transfascetal route in cases of bone fragments apposition and no hardware pullout in osteoporotic cases, no poly-methyl-methacrylate (PMMA) leakage through the fracture sites into the spinal canal, and no kyphotic deformities in both cases during follow-up periods. All patients demonstrated solid bony fusion except one following osteoporotic compression fracture on other sites. Conclusions : In the management of unstable thoraco-lumbar fracture, we believe that this short segment pedicle screw fixation with augmented intra-operative vertebroplasty reduce the total length or levels of pedicle screw fixation without post-operative kyphotic deformity.

• Korean Institute of Interior Design Journal
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• v.26 no.5
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• pp.65-74
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• 2017

The purpose of this research is to analyze characteristics of street elements when pedestrians have a view in the street. The research was utilized eye-tracking experiment and two times survey before and after experiment. The experiment is composed as follows. The data collection was conducted two days period from March 30 to 31, 2017. There were 43 participants who were all male and undergraduate students. In the data recording, the stimulus image was presented 65 seconds on a 23-inch monitor. Prior to analyzing data, the images were represented into five elements of AOI(area of interest). The fixation rate was divided by a period such as 'fixation time' and 'fixation count' parameters. The results were additionally obtained by linking analysis with the area ratio of AOI, time series analysis, and questionnaire. First of all, both building signs and advertisement standing boards draws attentions in participants. From a comparison between fixation rate and survey, the data have negative perspective view. Second, the advertisement standing boards are more eye-catching than other elements regardless of AOI size. It shows the priority of elements what should be developed in the environment. Third, the pavement is rarely seen in the fixation rate. Fourth, the trees are not a long frequency but viewed as a positive element. People want to keep the natural site in the street. In summative research, this method of extracting eye movement data would be provided a foundation data for developing streetscape plan based on scientific factors.