• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.2
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• pp.102-107
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• 2003

At orthodontic treatment, we have made every effort to get rigid anchorage which is not stirred when teeth move. As a result, the miniscrew that is rigid anchorage was invented recently, and now it is used widely. Concerning the advantage of miniscrew, it is reduced dependence of extraoral anchorage and it shortens treatment time for rapid tooth movement. In contrast, the defect of miniscrew is falling off it resulted from increasing of the mobility. So the purpose of this research is to be of help to prognose clinical use of miniscrew, which is inserted for intraoral anchorage, by investigating and comparing the failure rate of miniscrew for loading time. This study researches the failure rate of miniscrew for teeth movement at the orthodontic treatment. The failure rate of miniscrew in mid course, after inserting 147 miniscrews in 51 patients, is 13%(20/147). It showed no statistically significant differences as compared man with woman, maxilla with mandible, double-head with uni-head miniscrew, and drilling and non-drilling before inserting the miniscrew. In comparison below twenties with over twenties and the times that we give load to miniscrew, it produced that the failure rate of miniscrew is 9.7% higher in the case of below the twenties than over the twenties. Also, the failure rate of loading immediately is 10.8% higher than loading after 7 days. According to using driver for the insertion of miniscrew, the failure rate of miniscrew is higher in the case of using machined driver than in the case of using hand driver when the level of significance is 95%. According to the research, we can suppose that the failure rate has no concern with using miniscrew on man or woman, maxilla or mandible, the shape of head, and drilling or non-drilling before insertion of miniscrew. Therefore, we can choose eclectic miniscrew as demands. In addition, we must notify the patient, below twenties, to be possibility of high failure rate. And It is strongly recommended to give load after $1{\sim}2$ weeks for healing of the insertion area.

• Korean journal of communication and information
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• v.45
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• pp.255-295
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• 2009

The purpose of this study was to investigate how much multi-cultural traits the multiculture-oriented TV programs would have and how they tended to represent it with what kinds of meaning structures. As an object of this study, the authors chose the Program of KBS-TV which had been discussed seriously to raise a multi-cultural issue as well as a sexuality issue of lady guests. They collected 70 weekly programs from Nov. 26 of 2006 to March 31, 2008, and finally selected and analyzed 5 weekly programs as main analytic data. They tried to analyze them with various semiotic research methods, especially, linguistic semiotic research methods and pictorial research methods. As results of this study, it was found that this Program was based on multiful-levels of meaning structure: that is, superficial level, representation level and in-depth level. The superficial level of this program presented various multi-cultural traits through many and various talks of lady guests. Its representation level indicated some patterns of discourses about issues and agendas of the talks among lady guests. The in-depth level was based on the sexuality of lady guests as well as the male-dominant ideology. It was finally implicated that this Program was based on the sexuality and feminity of lady guests even though it tried to advocate its multi-cultural traits.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.1
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• pp.47-57
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• 2010

An undisturbed healing process without micromotion at the implant-bone interface is essential for achievement of osseointegration of dental implant. Therefore, initial stability was advocated as prerequisite for successful clinical outcome. Adequate bone quality and quantity were important to achieve initial stability and to prevent early failures. However there were few published data available regarding the effect of design change in implant geometry on initial stability of the implants. The purpose of the current study was to assess the initial stability of various designs of implants when placed into artificial bone materials of varying qualities and shapes of insertion holes. Within the scope of this study, the following results were drawn. Bone quality was major importance to achieve initial stability. Initial stability was higher on GS II which had additional design feature of double thread. With a tapered design of implant such as GS III showed a higher initial stability than straight one. An insertion hole with the similar shape of implant would lead to reduce a compression force on cortical bone and enhance a bone anchorage on cancellous bone.

• Journal of the Korean Chemical Society
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• v.48 no.5
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• pp.504-509
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• 2004

The reaction of Cu metal with mixed alkali metal polyselenide flux ($KNaSe_x$) produced large plate-like crystals of $KCu_4Se_3$. The structure of $KCu_4Se_3$, determined with X-ray single crystal diffraction techniques, is tetragonal (P4/mmm, a=4.013(1))${\AA}$, c=9.712(1))${\AA}$, z=1, R=6.7%). The structure is composed $[Cu_4Se_3]_n^{n-}$double layers which are made of fused anti PbO-type Cu2Se2 layers. Temperature variable resistivity measurement on single crystal of $KCu_4Se_3$ shows metallic behavior ranging from $1.8{\times}10^{-4}{\Omega}{\cdot}cm$ (at 300 K) to $1.0{\times}10^{-6}{\Omega}{\cdot}cm$ (at 20 K).

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10985-10989
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• 2015

Background: The capability for DNA double-strand breaks (DSBs) repair is crucial for inherent radiosensitivity of tumor and normal cells. We have investigated the clinicopathologic significance of DNA repair gene expression in nasopharyngeal (NP) carcinoma. Materials and Methods: A total of 65 NP cancer patients who received radiotherapy were included. The immunopositivity to Ku 70, DNA-PKcs, MRN, RAD50, XRCC4, and LIG4 were examined in all tumor tissues. Results: The patients comprised 42 males and 23 females, with a median age of 56 years (range, 18-84). The expression levels of RAD50 (0,+1,+2,+3) were 27.7%, 32.3%, 21.5%, and 18.5%. LIG4 (${\pm}$) were 43.1% and 56.9% respectively. The 5-year OS rate of patients with LIG4 (${\pm}$) were 90% and 67.9%, respectively (p=0.035). The 5-year TTP rate of patients with LIG4 (${\pm}$) were 75.9%, 55.5%, respectively (P=0.039). Conclusions: Our results suggest the possibility of predicting the radiosensitivity of NP cancer by performing immunohistochemical analysis of LIG4.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.5
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• pp.869-875
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• 2017

Using TCAD simulation, performances of tunnel field-effect transistors (TFETs) was investigated. Drain current-gate voltage types of TFET structure such as single-gate TFET (SG-TFET), double-gate TFET (DG-TFET), L-shaped TFET (L-TFET), and Pocket-TFET (P-TFET) are simulated, and then as dielectric constant of gate oxide and channel length are varied their subthreshold swing (SS) and on-current ($I_{on}$) are compared. On-currents and subthreshold swings of the L-TFET and P-TFET structures with high electric constant and line tunneling were 10 times and 20 mV/dec more than those of the SG-TFET and DG-TFET using point tunneling, respectively. Especially, it is shown that hump effect which dominant current element changes from point tunneling to line tunneling, is disappeared in P-TFET with high-k gate oxide such as $HfO_2$. The analysis of 4 types of TFET structure provides guidelines for the design of new types of TFET structure which concentrate on line tunneling by minimizing point tunneling.

• Journal of Haehwa Medicine
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• v.18 no.1
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• pp.19-28
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• 2009

Objectives: This study was conducted to help clinical studies for treating Functional Dyspepsia with acupuncture. We inspected tendency of studies of acupuncture treatment for functional dyspepsia and analyzed the assessing instrument for it by scrutinizing Pubmed recent publications. Materials and Methods: We inspected 8 theses and scrutinized their objectives, periods, participants, materials and methods, the instrument of assessment for the studies, and criteria and symptom score for questionaire, results and JADAD score. Results: 1. Most studies were published by oriental doctors except one which was published by an American doctor. More and more studies are being published in America and written in English recently. So it is considered that western doctors think that the acupuncture treatment is useful as unorthodox medicine for functional dyspepsia. 2. Among the 4 clinical studies, 2 studies were RCT and 1 study was not RCT and 1 study with vagueness. All 4 clinical studies were not double-blinded because they were about comparison between acupuncture treatment and medicine. 3. ST36, PC6, CV12, BL21 were chiefly used, and auricular point, ST40, SP6 were also used. Manual acupuncture were used in 2 studies, and low frequency pulse and electroacupuncture were used in other studies respectively. 4. 4 clinical studies used 0~3 points symptom score as the instrument of assessment. Additional assessments were on gastric emptying time, EGG and plasma level of motilin. All thesis were not verified of validity and reliability. 5. Among the 4 reviewed thesis, 2 theses were about acupuncture as one of the various treatment of functional dyspepsia, and the other 2 theses were about efficacy of acupuncture treatment. And the result generally showed effectivity of acupuncture treatment. Conclusion: Acupuncture treatment for functional dyspepsia is considered useful as in unorthodox medicine by western doctors, and it is necessary to provide objective instrument for assessing acupuncture treatment for functional dyspepsia.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.2
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• pp.165-173
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• 2006

Purpose: With gold electroforming system fir the double crown, the secondary crown is electroformed directly onto the primary crown. An even thick layer of high precision can be acquired. It is thought that the retention of electroformed outer crown is primarily acquired by the adhesive force (surface tension) through the saliva which is interposed between precisely fitted inner and outer crown. The purpose of this study was to investigate the effect of taper and surface area of inner crown on the retentive force of electroformed outer crown according to the presence of saliva. Materials and methods: 32 titanium inner crowns with cervical diameter of 8 mm and cone angles of 0, 2, 4, 6 degrees, which had same surface area by regulated height, were machined on a lathe. Another 32 titanium inner crowns with cone angles of 0, 2, 4, 6 degrees, which had doubled surface area by increased cervical diameter. were fabricated. Eight specimens of each group, for a total of 64 titanium inner crowns, were prepared. The electroformed outer crowns were fabricated directly on the inner crowns by using electroforming machine(GAMMAT free, Gramm Technik, Germany). The tertiary frameworks were waxed-up on the electroformed outer crown and cast using nonprecious alloy($Rexillium^(R)III,\;Jeneric^(R)/Pentronh^(R)$ Inc., USA). The cast metal frameworks were sandblasted with alubimium oxides and cemented using resin cement(Superbond C&B, Sun Medical Co., Japan) over the electroformed copings of each specimen. Then, artificial saliva($Taliva^(R)$, Halim Pharm. Co., Korea) was sprayed between the inner and outer crown, and they were connected under 5 kg force. The retentive force was measured by the universal testing machine(Tinius Olsen 1000, Tinius Olsen, USA) with a cross-head speed of 66.67 mm/sec. The direction of cross-head travel was exactly aligned with the path of removal of the respective specimens. This measurement procedures for retentive force of electroformed outer crown with artificial saliva were repeated in the same way without presence of artificial saliva. Results and Conclusion: The following conclusions were drawn: 1. The retentive force of electroformed outer crown was decreased according to increased taper of inner crown(P<.05). 2. The retentive force of electroformed outer crown showed no significant differences according to surface area and the presence of artificial saliva(P>.05).

• Journal of the Korean Geotechnical Society
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• v.27 no.11
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• pp.5-15
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• 2011

This paper presents two analysis methods for characterizing the non-linear finite strain consolidation behavior of highly deformable dredged soil deposits along with the fundamental parameters obtained in the companion paper; that is, the zero effective stress void ratio, the non-linear relationships of void ratio-effective stress and void ratio-hydraulic conductivity. The simplified Morris's analytical solution (2002) and the widely recognized numerical program, PSDDF (primary Consolidation, Secondary Compression, and Desiccation of Dredged Fill) for both single and double drainage conditions are adopted in this paper to verify a series of laboratory experiments for self-weight consolidation of the Incheon clay and Kaolinite. The comparisons show that the analysis methods proposed herein can properly simulate the long-term non-linear finite strain consolidation behavior for dredged soils in the field. In addition, a case study for the artificial Craney Island has been conducted to illustrate the importance of obtaining appropriate non-linear finite strain consolidation parameters and the applicability of PSDDF in promoting dredged soil disposal.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.1
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• pp.75-94
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• 2019

As the present single-layer repository concept requires too large an area for the site of the repository, a multi-layer repository concept has been suggested to improve the disposal density. The effects of the excavation damaged zone around the multi-layer repository constructed in the deep host rock on the temperature distribution in the repository were analyzed. For the thermal analysis of the multi-layer repository, the hydrothermal model was used to consider the resaturation process occurring in the buffer, backfill and rock. The existence of an excavation damaged zone has a significant effect on the temperature distribution in the repository, and the maximum peak temperatures of double-layer and triple-layer repositories can rise to $7^{\circ}C$ and $12^{\circ}C$, respectively depending on the size of the excavation damaged zone and the degree of decrease of the thermal conductivity. The dominant factor affecting the peak temperature in the multi-layer repository is the decrease of thermal conductivity in the excavation damaged zone, and the excavation damaged zone formed around the deposition hole has more significant effects on the peak temperature than does the excavation damaged zone formed around the disposal tunnel.