• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.238-239
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• 2017

Waterproofing is a very important process in terms of durability of buildings. The materials used for waterproofing work to protect the concrete structure from external deterioration factors. In particular, the waterproofing materials applied to the exterior of the concrete structure have various problems due to changes in the external environment and variables in the construction process. The waterproof layer is repeatedly dried and shrunk according to changes in the external moisture environment, and the surface may be deteriorated due to exposure to long-term sunlight. In the case of the roof waterproofing in the structure, the waterproof layer which does not have a sufficient curing period shows much swelling and floating phenomenon. These defects, such as swelling and lifting, account for most of the defects that occur in the waterproof layer of the concrete slabs. Generally, it is difficult to expect the same level of performance as the initial state even if the waterproofing work is repaired when a defect occurs. Therefore, it is possible to reduce the defects of the waterproof layer such as swelling and lifting by forming a waterproof layer which can be integrated with the concrete surface by using a polyurethane type waterproofing material having a relatively low defective ratio compared to other waterproofing materials. So in this study, the basic properties of polyurethane waterproof sheet reinforced with non-woven fabric are investigated in order to understand field applicability.

• Journal of Korean Foot and Ankle Society
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• v.10 no.2
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• pp.133-139
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• 2006

Purpose: To evaluate the results of mosaicplasty and microfracture after surgical treatments for symptomatic osteochondral lesion of talus (OLT) by second-look arthroscopy. Materials and Methods: 7 cases of mosaicplasty and 7 cases of microfracture were reviewed who undertook second-look arthroscopy at 6 months or one year after undertaking mosaicplasty or microfracture for OLT between December 2004 and October 2005. The mean age at first operation was 43.6 years (Range, 20-59) (Mosaicplasty; 43.9 years, Microfracture; 43.4 years). The mean size of cartilage defect was $15.0{\times}7.7\;mm$ in mosaicplasty and $7.1{\times}6.6\;mm$ in microfracture. Clinical outcomes were evaluated by Freiburg ankle score. Cartilage healing state was evaluated by Insall's classification for chondromalasia during second-look arthroscopy. Results: By the Freiburg ankle score, 9 ankles (6 in mosaicplasty, 3 in microfracture) had excellent and 5 (1 in mosaicplasty, 4 in microfracture) had good results at the times of second-look arthroscopy. By Insall's classification, consistency of the osteochondral grafts and congruity between grafts and native cartilage (Grade I) were shown in 9 (6 ankles in mosaicplasty, 3 ankles in microfracture), a fissuring (Grade II) in one ankle of mosaicplasty, a fasciculation (Grade III) in one ankle of microfracture, and partial exposure of subchondral bone (Grade IV) in 3 ankles of microfractures. Conclusion: Mosaicplasty was more excellent in consistency and hardness of cartilage than microfracture. In some cases of microfracture, cartilage healing was incomplete at 6 months postoperatively, so second-look arthroscopy is necessary to identify. If incomplete cartilage healing was shown, additional procedure such as microfracture or mosaicplasty was needed.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.5
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• pp.367-371
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• 2001

The chromosome 7-linked long QT syndrome (LQT2) is caused by mutations in the human ether-a- go-go-related gene (HERG) that encodes the rapidly activating delayed rectifier $K^+$ current, $I_{Kr},$ in cardiac myocytes. Different types of mutations have been identified in various locations of HERG channel. One of the mechanisms for the loss of normal channel function is due to membrane trafficking of channel protein. The decreased channel function in some deletion mutants appears to be due to loss of coupling with wild type HERG to form the functional channel as the tetramer. Most of missense mutants with few exceptions could interact with wild type HERG to form functional tetramer and caused dominant negative suppression with co-injection with wild type HERG showing variable effects on current amplitude, voltage dependence, and kinetics of activation and inactivation. Two missense mutants at pore regions of HERG found in Japanese LQT2 (A614V and V630L) showed accentuated inward rectification due to a negative shift in steady-state inactivation and fast inactivation. One mutation in S4 region (R534C) produced a negative shift in current activation, indicating the S4 serving as the voltage sensor and accelerated deactivation. The C-terminus mutation, S818L, could not express the current by mutant alone and did not show dominant negative suppression with co-injection of equal amount of wild type cRNA. Co-injection of excess amount of mutant with wild type produced dominant negative suppression with a shift in voltage dependent activation. Therefore, multiple mechanisms are involved in different mutations and functional abnormality in LQT2. Further characterization with the interactions between various mutants in HERG and the regulatory subunits of the channels (MiRP1 and minK) is to be clarified.

• Journal of Veterinary Clinics
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• v.15 no.2
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• pp.442-449
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• 1998

Freeze-dried cortical bones of the goat were transplanted to the experimental fibular defect of 10 dogs for valuating the possibility of xenogeneic bone implantation and the specificity of BM(Bone Morphogenetic Protein). The . freeze-dried cortical bone eliminated antigens and defatted with chloroform and methanol were freeze-dried at $-80{\circ}C$ for preservation of BMP and then sterilized with 50 gas and storaged in room temperature. Ten freeze-dried cortical implants of the goat were transplanted in experimentally defected regions of bilateral fibula of 5 dogs in clinically normal. The transplanted region had been radiographed for observing state of bone union and BALPOone Alkaline Phosphatase) in the serum of the host was measured for valuating activity of oteoblast per 2 week-interval after transplant procedures. New bone formation had been observed early in one of ten regions around implants about the same time as autoimplant regions. It was incorporated with its host bone during 4-12 weeks after transplantation. In another 2 cases of 2 dogs, new bone formation and absorption of implant had been observed from 4 weeks but they were not incorporated completely until 20 weeks. The rest of the freeze-dried bone implants, 7 cases of 4 dogs had not been observed new bone formation nor absorption of implants. The freeze-drying method for implants means to not influence bone incorporation. Although less of union percentages the union form of this experiment were similar to alloimplantation and it may mean to block immunity reaction that disturbs the bone induction by BMP. It demonsknted that the possibility of the xenogenous bone implantation is recognized by reason of the low specificity of BMP between goat and dog.

• Korean Journal of Materials Research
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• v.30 no.2
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• pp.61-67
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• 2020

BiFeO₃ with perovskite structure is a well-known material that has both ferroelectric and antiferromagnetic properties called multiferroics. However, leaky electrical properties and difficulty of controlling stoichiometry due to Bi volatility and difficulty of obtaining high relative density due to high dependency on the ceramic process are issues for BiFeO₃ applications. In this work we investigated the sintering behavior of samples with different stoichiometries and sintering conditions. To understand the optimum sintering conditions, nonstoichiometric Bi_1±xFeO_3±δ ceramics and Ti-doped Bi_1.03Fe_1-4x/3Ti_xO₃ ceramics were synthesized by a conventional solid-state route. Dense single phase BiFeO₃ ceramics were successfully fabricated using a two-step sintering and quenching process. The effects of Bi volatility on microstructure were determined by Bi-excess and Ti doping. Bi-excess increased grain size, and Ti doping increased sintering temperature and decreased grain size. It should be noted that Ti-doping suppressed Bi volatility and stabilized the BiFeO₃ phase.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.1
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• pp.226-252
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• 2002

The results of a literature study about the comparison of Oriental-Occidental medicine on the Atopic dennatitis were as follows. 1. In Oriental medicine, Atopic dermatitis belongs to the category of the Naesun(내선), Taeryumchang(胎斂瘡), Eczema(濕疹), Chimumchang(浸淫瘡). In Occidental medicine, the other names of Atopic dermatitis are allergic eczema, IgE dermatitis, flexual eczema etc. 2. In Oriental medicine, the definition of atopic dermatitis includes chang(瘡), sun(선), and pung(風). Occidental medicine, is one of the intrinsic eczema classifications. In fact eczema term circumscribes dermatitis in atopic patients. 3. In Oriental medicine, the etiology and pathogenesis of Atopic dermatitis arose from the state of cogenital defect(稟賦不足), internal accumulation of damp and heat(濕熱內蘊) at first, and then invaded pathogenic wind, damp, heat factors again, and combined endo-exoteric pathogenic factors. So it appears in skin. In Occidental medicine, the etiology and pathogenesis of Atopic dermatitis approaches in genetic, allergic and immunologic, pharmacophysioloic aspects. It is only a hypothesis but there is no known facts about radical aetiology. 4. In Oriental medicine, differentiation of syndromes classifies manifestation aspects, etiology and pathogenesis, and invasion period. In Occidental medicine, it divides into an invasion period, and clinical aspect etc. 5. In Oriental medicine, Internal theraphys of Atopic dermatitis are decoction of ingredients(湯劑), pills(丸), and tablet(片). So, it prescribes as treatments on the ground of differentition of syndrome. In Occidental medicine, there is no radical therapy because Atopic dispositions don't change. But steroid, antihistamine as symptomatic tre atments are generally used in Occidental medicine. 6. In Oriental medicine, external therapies are wet dressings(濕敷), lotion(洗劑), powder(散劑), adhesive plasters(膏劑), oil(油劑), smoking(烟薰法), warm over fire therapy(熱烘療法), acupunture and moxibustion therapy(鍼灸療法).

• Corrosion Science and Technology
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• v.7 no.1
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• pp.40-44
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• 2008

Passive metal forms an interfacial diffuse layer on the surface of passive film by its reaction with $H^+$ or $OH^-$ ions in solution depending on solution pH. There is a critical pH, called pH point of iso-selectivity ($pH_{pis}$) at which the nature of the diffuse layer is changed from the anion-permeable at pH<$pH_{pis}$ to the cation-permeable at pH>$pH_{pis}$. The $pH_{pis}$ for a passivated Fe was determined by examining the effects of pH on the thickness of passive film and on the dissolution reaction occurring on the passive film under a gavanostatic reduction in borate-phosphate buffer solutions at various pH of 7~11. The steady-state thickness of passive film formed on Fe showed the maximum at pH 8.5~9, and further the nature of film dissolution reaction was changed from a reaction producing $Fe^{3+}$ ion at $pH\leq8.5$ to that producing $FeO_2{^-}$ at $pH\geq9$, suggesting that the $pH_{pis}$ of Fe is about pH 8.5~9. In addition, the passive film formed at pH 8.5~9, $pH_{pis}$, was found to be the most protective with the lowest defect density as confirmed by the Mott-Schottky analysis. Pitting potential was decreased with increasing $Cl^-$ concentration at $pH\leq8.5$ due probably to the formation of anion permeable diffuse layer, but it was almost constant at $pH\geq9$ irrespective of $Cl^-$ concentration due primarily to the formation of cation permeable diffuse layer on the film, confirming again that $pH_{pis}$ of Fe is 8.5~9.

• Korean Journal of Materials Research
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• v.27 no.1
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• pp.48-52
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• 2017

In this study, we used I-V spectroscopy, photoconductivity (PC) yield and internal photoemission (IPE) yield using IPE spectroscopy to characterize the Schottky barrier heights (SBH) at insulator-semiconductor interfaces of Pt/$HfO_2$/p-type Si metal-insulator-semiconductor (MIS) capacitors. The leakage current characteristics of the MIS capacitor were analyzed according to the J-V and C-V curves. The leakage current behavior of the capacitors, which depends on the applied electric field, can be described using the Poole-Frenkel (P-F) emission, trap assisted tunneling (TAT), and direct tunneling (DT) models. The leakage current transport mechanism is controlled by the trap level energy depth of $HfO_2$. In order to further study the SBH and the electronic tunneling mechanism, the internal photoemission (IPE) yield was measured and analyzed. We obtained the SBH values of the Pt/$HfO_2$/p-type Si for use in Fowler plots in the square and cubic root IPE yield spectra curves. At the Pt/$HfO_2$/p-type Si interface, the SBH difference, which depends on the electrical potential, is related to (1) the work function (WF) difference and between the Pt and p-type Si and (2) the sub-gap defect state features (density and energy) in the given dielectric.

• Journal of Biomedical Engineering Research
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• v.20 no.3
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• pp.323-329
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• 1999

This paper proposed a method for the cancellation of the moving artifact which was produced during the detection of drowsiness usmg electrodermal activity signal. Two types of wrist electrode were developed to overcome the defect of the steering wheel type electrode which couldn't eliminate the moving artifacts due to driver's movements. Wrist type electrode II which has been modified from electrode type I was most effective for eliminating movmg artifacts compared to wheel type electrode and wrisL type electrode 1. The decIsion criteria(if IRI$\leq$10 and 1.1$\leq$dNz) for detecting moving artifact was determined from the virtual driving experiments. An algorithm which substituted past value of Nz for the current value of Nz whenever an EDA signal satisfied the criteria was developed. The experimental resulls of virtual driving and road test showed that the proposed algorithm had been successfully removed the most of the error due to the moving artifact Therefore, the developed system which use electrode type II and the algorithm might be less influenced by moving artifacts and could measure an accurate arousal state.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.4
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• pp.401-406
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• 1999

Secondary deformities of the lip and nose in individuals with repaired unilateral and bilateral clefts may vary in severity, depending on the state of the original defect, the care taken in the initial surgical procedure, the pattern of the patient's facial growth, and the effectiveness of interceptive orthodontic technique. Because each patient has a unique combination of deformities, their surgical reconstruction usually requires the modification and combination of several surgical techniques. Residual lip deformities after primary repair may be esthetic or functional and include scars, skin shortage or excess(vertical and transverse), orbicularis oris muscle malposition or diastasis. The key to accurate repair of secondary cleft lip deformities is a precise diagnosis. This requires observation of the patient in animation and repose. The quality of the scar is not the only factor determining the overall appearance of the lip. Observing the patient in the animated position is critical to assess muscular function. Factors that require precise analysis include lip length, the appearance of the Cupid's bow and philtrum, and nasal symmetry. Only after this detailed analysis can a decision be made as to wether a major or minor deformity exists. We report successful cases using various techniques for the secondary lip deformities.