• Journal of Periodontal and Implant Science
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• v.40 no.2
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• pp.76-85
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• 2010

Purpose: This study aimed to evaluate the effectiveness of the modified sinus floor elevation technique described hereafter as a "hybrid technique," in 11 patients with severely resorbed posterior maxillae. Methods: Eleven patients who received 22 implants in the maxillary premolar and molar areas by the hybrid technique were enrolled in this study. A slot-shaped osteotomy for access was prepared on the lateral wall along the lower border of the sinus floor. The Schneiderian membrane was fully reflected through the lateral slot. Following drilling with the membrane protected by a periosteal elevator, the bone was grafted. All implants were placed simultaneously with sinus augmentation. The cumulative success rate was calculated and clinical parameters were recorded. Radiographic measurements were performed. Results: All implants were well maintained at last follow up (cumulative success rate=100%). The mean residual bone height, augmented bone height, crown-to-implant ratio, and marginal bone loss were $4.1{\pm}1.64mm$, $8.76{\pm}1.77mm$, $1.21{\pm}0.34mm$, and $0.34{\pm}0.72mm$, respectively. Conclusions: Simultaneous implant placement with sinus augmentation by hybrid technique showed successful clinical results over a 2-year observation period and may be a reliable modality for reconstruction of a severely resorbed posterior maxilla.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.5
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• pp.428-436
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• 2013

Attrition characteristics of $CO_2$ absorbents for pre-combustion $CO_2$ capture were investigated to check attrition loss of those absorbents and to determine solid circulation direction and the better $CO_2$ absorbent. The cumulative attrition losses of two absorbents increased with increasing time. However, attrition loss under a humidified condition was lower than that under a non-humidified condition case. Between two absorbents, attrition loss of PKM1-SU absorbent was higher than that of P4-600 absorbent. The average particle sizes of the attrited particles were less than $2.5{\mu}m$ for two absorbents under a non-humidified condition case, and therefore, we could conclude that the main mechanism of attrition for two absorbents is not fragmentation but abrasion. Based on the results from the test for the effect of humidity on the attrition loss, we selected solid circulation direction from SEWGS reactor to regeneration reactor because the SEWGS reactor contains more water vapor than regeneration reactor. Attrition loss and make-up rate of two absorbents were compared based on the results from $CO_2$ sorption capacity tests and attrition tests. Required make-up rate of P4-600 absorbent was lower than that of PKM1-SU absorbent. However, more detail investigation on the optimum regeneration temperature, manufacturing cost, solid circulation rate, regeneration rate, and long-term sorption capacity should be considered to select the best $CO_2$ absorbent.

• Journal of Korean Society on Water Environment
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• v.30 no.5
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• pp.517-523
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• 2014

In order to remove both nitrate and sulfate present in the concentrate of RO(reverse osmosis) process, a combined bio-regeneration and ion-exchange(IX) system was studied. For this purpose, both denitrifying bacteria(DNB) and sulfate reducing bacteria(SRB) were simultaneously cultivated in a bio-reactor under anaerobic conditions. When the IX column containing a nitrate-selective A520E resin was fully exhausted by nitrate and sulfate, the IX column was bio-regenerated by pumping the supernatant of the bio-reactor, which contains MLSS concentration of $125{\pm}25mg/L$, at the flowrate of 360 BV/hr. Even though the nitrate-selective A520E resin was used, the breakthrough curves of ionic species showed that sulfate was exhausted earlier than nitrate. The reason for this result is due to the fact that the concentration of sulfate in RO concentrate was 36 to 48 times higher than nitrate. The bio-reactor was successfully operated at a volumetric loading rate of 0.6 g $COD/l{\cdot}d$, nitrate-N loading rate of 0.13 g $NO_3{^-}-N/l{\cdot}d$, and sulfate loading rate of 0.08 g $SO_4{^{2-}}/l{\cdot}d$. The removal rate of SCOD, nitrate-N, sulfate was 90, 100, and 85%, respectively. When the virgin resin was fully exhausted and consecutively bio-regenerated for 2 days, 81% of nitrate and 93% of sulfate were reduced. When the virgin resin was repeatedly used up to 4 cycles of service and bio-regeneration, the ion-exchange capacity of bio-regenerated resin decreased to 95, 91, 88, and 81% of virgin resin.

• Journal of Plant Biotechnology
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• v.40 no.4
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• pp.203-209
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• 2013

Genetic manipulation of pear (Pyrus pyrifolia Nakai) breeding is still difficult due to lack of reliable regeneration system. The aim of this research is to establish shoot regeneration system from leaf explants for pear (P. pyrifolia cv. Niitaka) using various concentrations of plant growth regulators and carbon source supplemented to medium. The highest regeneration rate of about 20% was found on a medium containing 4.4 g/L of Murashige and Skoog (MS) without vitamins, Linsmaier and Skoog (LS) vitamins were added separately. Leaf explants of pear were cultured on MS medium containing 7 g/L of Daishin agar supplemented with various concentrations of NAA (0.01, 0.05, 0.1, 0.5 mg/L) in combination with BA(3, 5, 10 mg/L) for shoot regeneration. In medium with 5 mg/L of BA and 0.01 mg/L of NAA, adventitious shoot regeneration rate was higher than others treated. The optimal results were observed using MS medium supplemented with 30 g/L sorbitol as carbon source on regeneration system. Sorbitol is considered better carbon source than sucrose for shoot regeneration of pear (P. pyrifolia cv. Niitaka). In order to increase of shoot regeneration in pear (P. pyrifolia cv. Niitaka), plant agar and Daishin agar used as gelling agents, Daishin agar is more efficient in shoot regeneration.

• Journal of Periodontal and Implant Science
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• v.27 no.1
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• pp.117-128
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• 1997

Using barrier membrane, guided bone regeneration(GBR) and guided tissue regeneration(GTR) of periodontal tissue are now widely studied and good results were reported. In bone regeneration, not all cases gained good results and in some cases using GTR, bone were less regenerated than that of control. The purpose of this study is to search for the method to improve the success rate of GBR and GTR by examination of the cause of the failure. For these study, rats and beagle dogs were used. In rat study, 5mm diameter round hole was made on parietal bone of the rat and 10mm diameter of bioresorbable membrane was placed on the bone defects and sutured. In 1 ,2, 4 weeks later, the rats were sacrificed and Masson-Trichrome staining was done and inspected under light microscope for guided bone regeneration. In dog study, $3{\times}4mm^2$ Grade III furcation defect was made at the 3rd and 1th premolar on mandible of 6 beagle dogs. The defects were covered by bioresorbable membrane extending 2-3mm from the defect margin. The membrane was sutured and buccal flap was covered the defect perfectly. In 2, 4. 8 weeks later. the animals were sacrificed and undecalcified specimens were made and stained by multiple staining method. In rats. there was much amount of new bone formation at 2 weeks. and in 4 weeks specimen, bony defect was perfectly dosed and plenty amount of new bone marrow was developed. In some cases, there were failures of guided bone regeneration. In beagle dogs, guided tissue regeneration was incomplete when the defect was collapsed by the membrane itself and when the rate of resorption was so rapid than expected. The cause of the failure in GBR and GTR procedure is that 1) the membrane was not tightly seal the bony defects. If the sealing was not perfect, fibrous connective tissue infiltrate into the defect and inhibit the new bone formation and regeneration. 2) the membrane was too tightly attached to the tissue and then there was no space to be regenerated. In conclusion, the requirements of the membrane for periodontal tissue and bone regeneration are the biocompatibility, degree of sealingness, malleability. space making and manipulation. In this animal study. space making for new bone and periodontal ligament, and sealing the space might be the most important point for successful accomplishment of GBR and GTR.

• Journal of Periodontal and Implant Science
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• v.31 no.1
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• pp.57-74
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• 2001

The purpose of this study was to evaluate the adjunctive combined effect of demineralized freeze-dried bone allograft(DFDB) in guided bone regeneration on supra-alveo-lar peri-implant defect. Supra-alveolar perio-implant defects, 3mm in height, each including 4 IMZ titanium plasma-sprayed implants were surgically created in two mongrel dogs. Subsequently, the defects were treated with 1 of the following 3 modalities: Control) no membrane or graft application, Group1) DFDB application, Group2) guided bone regeneration using an expanded polytetra-fluoroethylene membrane, Group3) guided bone regeneration using membrane and DFDB. After a healing period of 12-week, the animals were sacrificed, tissue blocks were harvested and prepared for histological analysis. Histologic examination were as follows; 1. New bon formation was minimal in control and Group 1, but considerable new bone formation was observed in Group 2 and Group 3. 2. There was no osteointegration at the implant-bone interface in the high-polished area of group2 and Group 3. 3. In fluorescent microscopic examination, remodeling of new bone was most active during week 4 and week 8. There was no significant difference in remodeling rate between group 2 and group 3. 4. DFDB particles were observed, invested in a connective tissue matrix. Osteoblast activity in the area was minimal. The results suggest that guided bone regeneration shows promising results in supra-alveolar peri-implant defects during the 12 week healing period although it has a limited potential in promoting alveolar bone regeneration in the high-polished area. There seems to be no significant adjunctive effect when DFDB is combined with GBR.

• Journal of Plant Biotechnology
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• v.7 no.4
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• pp.241-246
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• 2005

Factors affecting regeneration of different Rubus varieties (blackberry, raspberry and their hybrid) were examined and a reliable regeneration system was established. Media for stock plant maintenance were tested; different explants and media were investigated to find the best circumstances for the regeneration. The effect of the commonly used antibiotics was studied to determine the most suitable one for selection of the transformants. We found that both MS and LS media supplemented by $20\;gL^{-1}$ sucrose are suitable for the stock plant maintenance. The optimal hormone content for the stock plants is $0.125\;mgL^{-1}$ 6-benzylaminopurine (BAP) with $0.01\;mgL^{-1}$ indole-3- butyric acid (IBA). The highest regeneration rate was observed on medium containing MS salts with B5 vitamins complemented with glucose, sucrose, maltose, $10\;gL^{-1}$ each, supplemented with benzylaminopurine riboside (BAR) ($2\;mgL^{-1}$) and indole-3-acetic acid (IAA) ($0.1\;mgL^{-1}$). The regenerated shoots appeared directly from the cut edges, without callus phase. Hygromycin and geneticin proved to be good selection agents for the Rubus explants, but due to their severe effect on the tissues we propose to use marker-free constructions for the transformation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.3
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• pp.267-272
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• 1998

We confirmed conditions for callus formation and plant regeneration of five varieties of orchardgrass (Dactylis glomerma L.). Among five varieties of orchardgrass, "Hapsung 19" expressed the highest rate for both of callus formation and plant regeneration. Otherwise, among SH (Schenk and Hildebrandt), MS (Murashige and Skoog) and N6 medium (Chu), MS and N6 medium were highest degree of efficiencies in callus formation and plant regeneration, respectively. In this study, we determined volume of hormones appended in media; $3\;mg/\;{\ell}$ ofdicamba for callus formation and $1\;mg/\;{\ell}$ of NAA (I-naphtalene acetic acid) and $5\;mg/\;{\ell}$ kinetin (6-furfurylaminopurine) for plant regeneration were appended in their media. We obtained orchardgrass plants from callus about 50~80 days after transferred to regeneration media.ation media.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.2
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• pp.168-177
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• 1998

The effects of the regeneration parameters such as inlet gas temperature, space velocity, oxygen concentration of the exhaust gas, and initial particulate loading on the oxidation of the particulate inside ceramic cordierite filter have been investigated through an engine experiment. As the inlet gas temperature increases, the remarkable filter temperature occurs owing to the rapid combustion rate. Though the higher space velocity affirms the safe regeneration, it also requires much fuel consumption of the burner. For that reason, the space velocity should be compromised considering the fuel economy. The excessive accumulation of the particulate may cause undesirable regeneration temperatures inside filer even under the optimized regeneration condition. The inlet gas temperature should be selected to overcome the variation of the oxygen concentration which is inherent feature of the diesel engine. It is the most important factor in the regeneration control techniques.

• Journal of Energy Engineering
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• v.20 no.4
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• pp.286-291
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• 2011

The hybrid vehicle has a good fuel economy with a electric type braking energy regeneration system. This paper introduced a novel pneumatic type braking energy regeneration system. The novel system use a scroll mechanism which have both compression function and expansion function. While vehicle is decelerating, the scroll machinery, being operated as a scroll compressor, compress a atmospheric air to save the vehicle's kinetic energy and reuse a compressed air which is reserved in a air tank while vehicle is accelerating. In order to analyze fuel improvements by applying braking energy regeneration system to a vehicle, we simulated the rate of braking energy regeneration through CVS-75 mode driving patterns.