• YAKHAK HOEJI
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• v.43 no.2
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• pp.150-159
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• 1999

Hollow type suppositories inserted polyvinyl alcohol (PVA) hydrogel capsule containing propranolol·HCI (PPH) were prepared using different bases, polyethylene glycol (PEG), Witepsol H-15 (WH-15) and Witepsol W-35 (WW-35) to improve the controlled release of PPH. The release of PPH from the hollow type suppository inserted PVA hydrogel capsule was retarded than that from PEG, WH-15, or WW-35 hollow type suppositories in rat rectal cavity. When the suppositories were administered to rats, the controlled release of PPH was proved by the plasma concentration-time-profiles of PPH. No significant difference (p〈0.05) among the three different hollow type suppositories was observed in terms of AUC and MRT of PPH. WH-15 hollow type suppository inserted 12% of PVA hydrogel capsule caused irritation to rat rectal mucosa. However, the WH-15 hollow type suppository inserted PVA hydrogel capsule caused no severe irritation on rectal mucosa. The application of the hollow type suppositories using PVA in sustained rectal delivery of drugs might be feasible.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.7
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• pp.320-326
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• 2003

Slotless Permanent Magnet Linear Synchronous Motor (PMLSM) has good control ability but thrust density is low. So, this paper proposes inserted core type of slotless PMLSM to improve its thrust density. Inserting the core between windings of each phase, detent force is generated by the difference of magnetic resistance in an air gap. To minimize detent force, this paper applies the neural network to inserted core type of slotless PMLSM. The, Magnetic pole ratio, the width of the inserted core and the width of the coil are selected as a design parameter to minimize detent force. In comparison with inserted core type one, thrust ripple greatly decreases by minimizing detent force and also thrust increases in this optimal model.

• Environmental Engineering Research
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• v.16 no.2
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• pp.91-96
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• 2011

Limited information is available on the degradation of volatile hydrocarbons determined via the use of plate-inserted photocatalytic reactors. This has led to the evaluation of surface areas of cylindrical continuous-flow photocatalytic reactors for the degradation of three selected aromatic hydrocarbons. Three types of reactors were prepared: a double cylinder-type, a single cylindrical-type without plates and a single cylindrical-type with inserted glass tubes. According to diffuse reflectance, FTIR and X-ray diffraction (XRD) spectroscopy, the surface characteristics of a coated photocatalyst were very similar to those of raw $TiO_2$, thereby suggesting that the coated photocatalyst exhibited the same photocatalytic activity as the raw $TiO_2$. The photocatalytic degradation efficiencies were significantly or slightly higher for the single cylinder-type reactor than for the double cylinder-type reactor which had a greater catalytic surface area. However, for all target compounds, the degradation efficiencies increased gradually when the number of plates was increased. Accordingly, it was suggested that the surface area being enhanced for the plate-inserted reactor would elevate the photocatalytic degradation efficiency effectively. In addition, this study confirmed that both initial concentrations of target compounds and flow rates were important parameters for the photocatalytic removal mechanism of these plate-inserted photocatalytic reactors.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.9
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• pp.525-531
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• 2004

This paper proposes inserted core type of slotless Permanent Magnet Linear Synchronous Motor(PMLSM) to improve its low thrust density. However, by inserting the core between windings of each phase, detent force is generated and it acts as thrust ripple. Furthermore, linear motors generate end effect making thrust ripple. So, this paper applies the neural network to minimize detent force and to maximize thrust. Also, sub-poles is placed at the end parts of the mover to compensate end effect. To confirm of calculation method's validity, the calculated results are compared with experimental results.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.242-248
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• 2002

Previously, it was reported that the nonhomologous C-terminal regions of the D-hydantoinases are nonessential for catalysis, but affect the oligomeric structure of the enzyme [3]. In an effort to further confirm the above observation, the C-terminal region-inserted enzyme was constructed by attaching a peptide (22 residues) at the C-terminal of the D-hydantoinase from Bacillus thermocatenulatus GH2, and its structural and biochemical properties were compared with both the wild-type and C-terminal region-truncated enzymes. As a result, native tetrameric D-hydantoinase was dimerized as the truncated enzyme, and the inserted mutant with a new sequence was expressed as a catalytically active form in E. coli. Expression level of the inserted and truncated enzymes were found to be significantly increased compared to the level of the wild-type enzyme, and this appears to be due to the reduced toxic effect of the mutant enzymes on host cells. Dimerized enzymes exhibited increased thermo- and pH stabilities considerably when compared with the corresponding wild-type enzyme. Comparison of the substrate specificity between the mutant and wild-type enzymes suggests that the substrate specificity of the D-hydantoinase is closely linked with the oligomeric structure.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.2
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• pp.97-103
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• 2016

When chewing forces are repetitively applied to a dental implant, gaps are often generated at the interface surfaces between the abutment and the fixture, which results in some deterioration, such as loosening of the fastening screw, dental retraction, and fixture fractures. To cope with such problems, a sealing-type abutment having a number of grooves along the conical-surface circumference was previously developed, and it showed better sealing performance than conventional ones. To enhance the sealing performance, a new model in which a gold ring is inserted into the top groove of the sealing-type abutment is developed in this study. In addition, a manufacturing process is developed, and performance evaluations, such as fatigue and sealing tests, are carried out. The evaluation results show that the gold-ring-inserted sealing abutment yields better performance than conventional ones.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.6
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• pp.455-464
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• 2004

The purpose of this study was to evaluate and compare the influence of Steroid topical irrigation and implant surface on bone healing in the irradiated rabbit tibia. Implant to bone contact surface ratio and the pattern of bone healing around hydroxyapatite(HA) coated implant and pure titanium (Ti) implant which were inserted into the irradiated rabbit tibia were compared. 16 Korean house mature male rabbits were used as experimental animal. Each rabbit received 15 Gy of irradiation. 4 weeks after the irradiation, two holes were prepared in the irradiated tibia of each rabbits, where two surface type of implants were inserted :1) HA coated type and 2) pure Ti type. Right before placing implants, one group of rabbit received steroid irrigation and the other group did saline. After the irrigation, two implants of HA coated type and pure Ti type were inserted into the tibia of each rabbits. Each rabbit were sacrificed at 2nd, 4th, and 8th week after the implantation and the specimens were observed by the light microscope. The pattern of bone healing and histomorphometric analysis of the implant-bone interface were done. The results were as follows. 1. All implants inserted into the irradiated tibia of rabbit did not show any sign of clinical mobility and the bone around implants inserted into the irradiated tibia of rabbit did not show any resorption. 2. The bone to implant contact surface ratio around HA coated implants that received steroid irrigation got more bone to implant contact surface ratio than that of the saline irrigation. This result showed statistically significant(p<0.05). There was no statistically significant difference in 8th week group. 3. Though there was no statistically significant difference HA coated implants had more bone to implant contact surface ratio than pure Ti implant in 2nd and 4th groups, and there was no difference in 8th week group. 4. All implants inserted into the irradiated tibia of rabbit had exhibited successful osseointegraion.

• Journal of Korean Association for Spatial Structures
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• v.20 no.2
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• pp.39-49
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• 2020

In this study, we will develop a hybrid cross-sectional shape of steel inserted type glued-laminated timber that can improve the strength of structural glued-laminated timber and maximize the ductility by using steel plate with excellent tensile and deformation ability. A total of three specimens were fabricated and the flexural performance test was carried out to evaluate the structural performance of the steel inserted type glued-laminated timber. In order to compare the effect of steel inserted glued-laminated timber, one structural glued-laminated timber test specimen composed of pure wood was manufactured. In addition, in order to evaluate the adhesion performance of the steel inserted, one each of a screw joint test specimen and a polyurethane joint test specimen was prepared. As a result, all the specimens showed the initial crack in the finger joint near the force point. This has been shown to be a cause of crack diffusion and strength degradation. The use of finger joints in the maximum moment section is considered to affect the strength and ductility of the glued-laminated timber beam. Polyurethane-adhesive steel inserted glued-laminated timber showed fully-composite behavior with little horizontal separation between the steel plate and glued-laminated timber until the maximum load was reached. This method has been shown to exhibit sufficient retention bending performance.

• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.69-78
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• 2008

Shearing strength test in tension type was investigated to determine the shear resistance of bolt and drift-pin connection of domestic larix glulam. The specimen was connected with bolt and drift-pin in the inserted plate type, and only bolt in the side plate type. The diameter of bolt and drift-pin used in the experiment are 12, 16 and 20 mm. The hole of bolt was drilled at the end-distance 5 d and 7 d. Tension load was loaded in the direction parallel to grain. The shear resistance was evaluated according to end-distance through this, the yield load was compared with the experimental yield load, using Larsen's formula. The prototype design strength is based on the yield load of end-distance 7 d and the reduction factor of end-distance 5 d was calculated. The results were as follows. 1. The average of maximum load of drift-pin connection was higher by 3~30% at the inserted type than at bolt connection with increasing diameter. In bolt connection, the average of maximum load of the side type was 1.54~2.07 times higher than that of the inserted type. In the same diameter, the average of maximum load of end-distance 7 d was higher by 8~44% than that of 5 d. 2. The bearing stress was 1.16~1.41 times higher at the inserted connection than at drift-pin connection, and 1.37~1.86 times higher at 7 d than at 5 d. Also, when the slenderness ratio was below 7.5 at drift-pin connection and below 6.0 at inserted connection, the lateral capacity was good. 3. The ratio of the experimental yield load and the predicted yield load calculated by Larsen's formula proposed by Larsen was 0.80~1.10 at inserted connection, and 0.75~1.46 at side connection. 4. When the inserted bolt connection was based on the yield load of end-distance 7 d, the reduction factor was 0.89 at 12 mm connection, 0.93 at 16 mm and 0.85 at 20 mm. The reduction factor was 0.89 at 12 mm the inserted drift-pin connection, 0.93 at 16 mm, 0.93 at 20 mm. The reduction factor was 0.79 at the side connection of the 12 mm bolt connection and 0.80 at 16 mm.

• Korean Journal of Optics and Photonics
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• v.5 no.1
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• pp.80-83
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• 1994

A Littman type dye laser oscillator inserted a wedge prism was constructed. Accurate frequency tuning was achieved by the rotation of the wedge prism instead of the tuning mirror. Frequency tuning rate was about 20 GHz/deg. and the synchronous tuning of 70 GHz without mode-hop was achieved. ieved.