• Journal of Periodontal and Implant Science
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• v.36 no.1
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• pp.27-37
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• 2006

Although the main purpose of periodontal treatment to regenerate is the complete regeneration of periodontal tissue due to periodontal disease, most of the treatment cannot meet such purpose because healing by long epithelial junction. Therefore, diverse materials of resorbable and non-resorbable have been used to regenerate the periodontal tissue. Due to high risk of exposure and necessity of secondary surgical procedure when using non-resorbable membrane, guided tissue regeneration using the resorbable membrane has gain popularity, recently. However, present resorbable membrane has the disadvantage of not having sufficient time to regenerate date to the difference of resorption rate according to surgical site. Meanwhile, other than the structure stability and facile manipulation, acellular dermal matrix has been reported to be a possible scaffold for cellular proliferation due to rapid revascularization and favorable physical properties for cellular attachment and proliferation. The purpose of this study is to estimate the influence of acellular dermal matrix on periodontal ligament, cementum and alveolar bone when acellular dermal matrix is implanted to 1-wall alveolar bone defect. 4 dogs of 12 to 16 month old irrelevant to sex , which below 15Kg of body weight, has been used in this study. ADM has been used for the material of guided tissue regeneration. The 3rd premolar of the lower jaw was extracted bilaterally and awaited for self-healing. subsequently buccal and lingual flap was elevated to form one wall intrabony defect with the depth and width of 4mm on the distal surface of 2nd premolar and the mesial surface of 4th premolar. After the removal of periodontal ligament by root planing. notch was formed on the basal position. Following the root surface treatment, while the control group had the flap sutured without any treatment on surgically induced intrabony defect. Following the root surface treatment, the flap of intrabony defect was sutured with the ADM inserted while the control group sutured without any insertion. The histologic specimen was observed after 4 and 8 weeks of treatment. The control group was partially regenerated by periodontal ligament, new cementum and new alveolar bone. the level of regeneration is not reached on the previous formed notch. but, experimental group was fully regenerated by functionally oriented periodontal ligament fiber. new cementum and new alveolar bone. In conclusion, we think that ADM seems to be used by scaffold for periodontal ligament cells and the matrix is expected to use on guided tissue regeneration.

• Journal of Korean Association for Spatial Structures
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• v.11 no.4
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• pp.79-88
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• 2011

Recently, complex-shaped tall buildings represented by 3T(Twisted, Tapered, Tilted) are planed largely. A diagrid structural system is one of the most widely used structural system for complex-shaped tall buildings because of its structural efficiency and formativeness. Plans for tilted tall buildings are largely presented because of beauty of a sculpture and many of buildings use diagrid structural systems. Lateral displacements of tilted tall buildings are induced by not only lateral loads but also self weight. Therefore, reduction of lateral responses of tilted tall buildings is as important as typical tall buildings. In this study, a smart TMD is introduced to reduce seismic responses of tilted diagrid tall buildings and its control performance is evaluated. MR damper is employed for the smart TMD and ground-hook controller is used as a control algorithm for the smart TMD. 100-story tall building is used as an example structure. Control performances of uncontrolled case, controlled case with TMD and controlled case with smart TMD are compared and investigated. Numerical simulation has shown that smart TMD presented good control performance for displacement response but acceleration response was not controlled well.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.651-661
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• 2008

The mother's obesity-related stress and it's association with obesity, food intake, and physical activity in both mothers and their children were determined. Based on self-reports from 470 mothers, obesity stress of mothers were scored by using a five-point Likert scale; only low and high stress scores were used in this study. The perceptions of mothers' weights and their children's weights, mothers' Body Mass Indices (BMI), and preschoolers' Weight-Length Indices (WLI)(%) were also determined. The obesity stress of mothers was significantly associated with the mothers' BMI (high stress: $23.5{\pm}2.4$ vs. low stress: $19.6{\pm}1.7$, p<0.05), but not with their children's obesity. Mothers with a high obesity stress reported a higher percentage of family history of obesity (62.1% vs. 38.3%, p<0.001) than mothers with low obesity stress. Compared to mothers with low obesity stress, mothers with high stress had lower correct-perceptions about their weights (p<0.05) but higher correct-perceptions for their children's weights. Almost 54.5% of mothers with high stress reported watching television 2 or more extra hours per day, compared with 32.2% of mothers with low stress (p<0.05). More children of mothers with high stress had long hours of daily TV viewing than children of mothers with low stress (36.0% vs. 15.3%, $X^2=10.491$, p<0.05). Mothers with high stress reported lower intake of protein-rich foods (p=0.01) and vegetables (p=0.039), but a higher intake of snacks (p=0.009), compared to mothers with low stress. More children of mothers with high stress reported eating high fat snacks or high sugar snacks everyday, but this was not statistically significant. In conclusion, high obesity stress in mothers were greatly associated with their BMI and their inactive life style, including long TV viewing hours per day and unbalanced food intakes, which can lead their children becoming inactive and obese. Special attention is recommended for overstressed mothers and their children, especially those who enjoy long hours of TV viewing.

• Journal of Yeungnam Medical Science
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• v.7 no.2
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• pp.79-87
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• 1990

Using Zung's self-rating depression scale, the authors studied depression in 310 elderlies residing in the 9 home for the aged (HFA) in Kyungbuk area, and 234 elderlies living in Taegu city and 107 elderlies attending a Life-long education program in Taegu, which serve as a control group, Community resident elderlies(CRE). The research had been administered during the period from June to August, 1986. The results were as follows : 1. The mean scores of male. female. and the total of the elderlies in HFA were $38.95{\pm}11.55$, $44.18{\pm}14.15$:: and $42.8{\pm}13.7$ respectively while CRE marked $40.8{\pm}11.3$ for male, $45.2{\pm}12.0$ for female, and $43.4{\pm}11.9$ for the total. Therefore there were significant differences between male and female in both groups(p<0.01, p<0.001), though no significant difference between the two groups. However, the depression score of elderlies in HFA might be much higher than that of CRE if 81 elderlies(14.2%) in HFA who had been left out of the statistical evaluation due to their having severe depression, organic brain syndrom, or pseudoementia, etc had been included. 2. The score distribution by items for the elderlies in HFA were from highest scores hopelessness, worthlessness, emptiness, decreased appetite, confusion, while for CRE, hopelessness, decreased appetite, psychomotor retardation, indecisiveness, and worthlessness. Elderlies in HFA showed significantly high scores in depressed mood, weight loss, suicidal rumination(ideation) and psychomotor excitement, while CRE showed significantly high scores in decreased appetite, psychomotor retardation, indecisiveness, and dissatisfaction. 3. Elderlies who scored over 50 numbered 10 males(16%), 57 females(34%), and total of 67(29%) in HFA and 28 males(21%), 77 females(37%), and total of 105(31%) in CRE : female showed higher seores in both groups. 4. Psychosocial factors such as getting older(respectively p<0.01, p<0.01), being Buddhist(respectively p<0.01, p<0.01), and monthly pocket money less than \30,000(respectively p<0.001, p<0.001) were found to have a noticable impact on the depression level of the elderlies in both groups. Factors such as illiteracy (p<0.001, monthly pocket money less than \10,000(p<0.05), and having no family(p<0.01) recorded significantly higher scores among CRE than the elderlies in HFA.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.3 no.1
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• pp.147-157
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• 1992

The fragile X syndrome, which is considered to be synonymous with the Martin-Bell syndrome, is a relatively common form of X-linked mental retardation. The syndrome seems to occure in many different ethnic groups and its prevalence among mentally retarded males has been estimated to be in the order of 2 to 6%. The karyotypic hallmark of the syndrome is made up with a pronounced constriction near each tip of the long arm of the X chromosome(fragile site), shown in vitro only under conditions in which thymidylate production is blocked(lowered folate levels). Special culture media are needed to demonstrate this constriction site. Major clinical features associated with the syndrome include macroorchidism, large or prominent ears, significant emotional and behavioral dysfunctions such as hyperactivity, self-injury, lack of eye contact and social interaction, schizophrenia, autism, etc., and speech and language dysfunctions ranging from nonverbal to verbal speech with moderate to severe expressive language delays. Some have minor clinical features in common such as an increase in birth weight high forehead, prognathism, increased head circumference in infancy and childhood which did not persist into adult life. The recent research findings have shown that the fragile X syndrome is associated with infantile autism. Many patients with the fragile X syndrome fulfill the diagnostic criteria for infantile autism. Therefore it is recommendable that any patient with developmental delays and autism or autistic manifestations should have a chromosomal analysis, including fragile X examination. In the present review, historical aspects, incidence, and clinical features are presented. Recent anecdotal reports of the association with autism and the clinical improvement following high dose folic acid treatment will be discussed.

• Journal of the Earthquake Engineering Society of Korea
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• v.15 no.2
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• pp.53-60
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• 2011

When designing building structures, dynamic serviceability is one of the most important items. Much research is being carried out on machine vibrations that affect inside residents and expensive equipment in the building structure. The vibration effect generally depends on the mass ratio, and an adequate mass ratio is determined by comparison with the serviceability limit according to the criteria. This study investigates the evaluation of vibration serviceability by using ISO 2631 to confirm the propriety of adequate mass ratios and it is verified that the application of a complicated FE model to model the real large shaking table facility with the mathematical model simulated as a SDOF system. The weighted RMS value is then compared with the comfort limit given by ISO 2631. As a result, the analysis of the numerical model is consistent with analysis of the FE model. Moreover, it is found that the adequate mass ratio of the concrete foundation and shake table, considering the self-weight of the real facility, should be less than 0.013. It is also confirm that the sample facility is satisfies the requirement of an adequate mass ratio.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.469-474
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• 2002

In recent years, modularization of engine parts has increased the application of plastic products in air intake systems. Plastic intake manifolds provide many advantages including reduced weight, contracted cost, and lower intake air temperatures. These manifolds, however, have some weakness when compared with customary aluminium intake manifolds, in that they have low sound transmission loss because of their lower material density. This low transmission loss of plastic intake manifolds causes several problems related to flow noise, especially when the throttle is opened quickly. The physical processes, responsible for this flow noise, include turbulent fluid motion and relative motion of the throttle to the airflow. The former is generated by high-speed airflow in the splits between the throttle valve and the inner-surface of the throttle body and surge-tank, which can be categorized into the quadrupole source. The latter induces the unsteady force on the flow, which can be classified into the dipole source. In this paper, the mechanism of noise generation from the turbulence is only investigated as a preliminary study. Stochastic noise source synthesis method is adopted for the analysis of turbulence-induced, i.e. quadrupole noise by throttle at quick opening state. The method consists of three procedures. The first step corresponds to the preliminary time-averaged Navier-Stokes computation with a $k-\varepsilon$ turbulence model providing mean flow field characteristics. The second step is the synthesis of time-dependent turbulent velocity field associated with quadrupole noise sources. The final step is devoted to the determination of acoustic source terms associated with turbulent velocity. For the first step, we used market available analysis tools such as STAR-CD, the trade names of fluid analysis tools available on the market. The steady state flows at three open angle of throttle valve, i.e. 20, 35 and 60 degree, are numerically analyzed. Then, time-dependent turbulent velocity fields are produced by using the stochastic model and the flow analysis results. Using this turbulent velocity field, the turbulence-originated noise sources, i.e. the self-noise and shear-noise sources are synthesized. Based on these numerical results, it is found that the origin of the turbulent flow and noise might be attributed to the process of formulation and the interaction of two vortex lines formed in the downstream of the throttle valve. These vortex lines are produced by the non-uniform splits between the throttle valve and inner cylinder surface. Based on the analysis, we present the low-noise design of the inner geometry of throttle body.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.1
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• pp.1-7
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• 2013

Structural design and analysis of a coiling arm unloading machine for submarine cable have been originally conducted in this study. Three-dimensional CAD modeling process is practically applied for the structural design in detail. Finite element method(FEM) and multi-body dynamics(MBD) analyses are also used to verify the safety and required motions of the designed coiling arm structure. The effective moving functions of the designed coiling arm with respect to rotational and radial motions are achieved by adopting bearing-roller mechanical parts and hydraulic system. Critical design loading conditions due to its self weight, carrying cables, offshore wind, and hydraulic system over operation conditions are considered for the present structural analyses. In addition, possible inclined ground conditions for the installation of the designed coiling arm are also considered to verify overturn stability. The present hydraulic type coiling arm system is originally designed and developed in this study. The developed coiling arm has been installed at a harbor, successfully tested its operational functions, and finished practical unloading mission of the submarine cable.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.1
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• pp.55-63
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• 2013

Applications of nano-emulsion for cosmetics as a means of promoting dermal absorption have been the subject of interest. In this study, the stability of nano-emulsions prepared by low-energy emulsification method and varying the composition of raw materials was investigated. By measuring the particle size of the nano-emulsion against time, the stability of nano-emulsions prepared by adding polyol to water phase was increased significantly compared with the nano-emulsions prepared by adding polyol to ethanol phase. The speed of adding ethanol phase to water phase did not have a significant impact on the particle size and stability. Depending on the type of oil, stability was not affected. However, there would be a correlation between the initial size of the nano-emulsion droplets and the molecular weight and polarity of the oil. Stability and the initial particle size according to the type of polyols showed a similar trend except 1,2 hexanediol. The initial droplet size was affected by the concentration of surfactant and oil. However, the initial droplet size did not change against time. Concentration of ethanol was observed to have a significant impact on the initial particle size and stability.

• Journal of the Korean Vacuum Society
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• v.19 no.2
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• pp.81-90
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• 2010

We introduce a novel and versatile approach for preparing self-assembled nanoporous multilayered films with antireflective properties. Protonated polystyrene-block-poly (4-vinylpyrine) (PS-b-P4VP) and anionic polystyrene-block-poly (acrylic acid) (PS-b-PAA) block copolymer micelles (BCM) were used as building blocks for the layer-by-layer assembly of BCM multilayer films. BCM film growth is governed by electrostatic and hydrogen-bonding interactions between the oppositely BCMs. Both film porosity and film thickness are dependent upon the charge density of the micelles, with the porosity of the film controlled by the solution pH and the molecular weight (Mw) of the constituents. PS7K-b-P4VP28K/PS2K-b-PAA8K films prepared at pH 4 (for PS7K-b-P4VP28K) and pH 6 (for PS2K-b-PAA8K) are highly nanoporous and antireflective. In contrast, PS7K-b-P4VP28K/PS2K-b-PAA8K films assembled at pH 4/4 show a relatively dense surface morphology due to the decreased charge density of PS2K-b-PAA8K. Films formed from BCMs with increased PS block and decreased hydrophilic block (P4VP or PAA) size (e.g., PS36K-b-P4VP12K/PS16K-b-PAA4K at pH 4/4) were also nanoporous. Furthermore, we demonstrate that the nanostructured electrochemical sensors based on patterning methods show the electrochemical activities. Anionic poly(styrene sulfonate) (PSS) layers were selectively and uniformly deposited onto the catalase (CAT)-coated surface using the micro-contact printing method. The pH-induced charge reversal of catalase can provide the selective deposition of consecutive PE multilayers onto patterned PSS layers by causing the electrostatic repulsion between next PE layer and catalase. Based on this patterning method, the hybrid patterned multilayers composed of platinum nanoparticles (PtNP) and catalase were prepared and then their electrochemical properties were investigated from sensing $H_2O_2$ and NO gas. This study was based on the papers reported by our group. (J. Am. Chem. Soc. 128, 9935 (2006); Adv. Mater. 19, 4364 (2007); Electro. Mater. Lett. 3, 163 (2007)).