• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.153-153
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• 2017

The application of the coating supports the mechanical characteristics of the implant, and various materials and coatings are currently being used in the implant in a way to accelerate adhesion. Especially, plasma electrolytic oxidation (PEO) coating has been proposed continually with good surface treatment of titanium alloys. Also, the PEO process can incorporate Ca and P ions on the titanium surface through variables varied factor. PEO process for bioactive surface has carried out in electrolytes containing Ca and P ions. Natural bone is composed of mineral elements such as Mg, Si, Zn, Sr, and Mn, etc. Especially, Mg and Si of these elements play role in bone formation and growth after clinical implantation of bio-implants. In this study, corrosion charateristics of PEO-treated Ti-6Al-4V alloy in solution containing Si and Mg ions has been investigated using several experimental techniques. The PEO-treated surfaces were identified by X-ray diffraction, using a diffractometer (XRD, Philips X' pert PRO, Netherlands) with Cu $K{\alpha}$ radiation. The morphology was observed by field-emission scanning electron microscopy (FE-SEM, Hitachi 4800, Japan) and energy-dispersive X-ray spectroscopy (EDX, Oxford ISIS 310, England). The potentiodynamic polarization and AC impedance tests for electrochemical degradations were carried out in 0.9% NaCl solution at similar body temperature using a potentiostat with a scan rate of 1.67mV/s and potential range from -1500mV to + 2000mV.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.154-154
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• 2017

Ti-6Al-4V alloys are widely used as metal-lic biomaterials in dentistry and orthopedics due to its excellent biocompatibility and me-chanical properties. However, because of low biological activity, it is difficult to form bone growth directly on the surface of titanium implants. For this reason, surface treatment of plasma electrolytic oxidation(PEO) was used for dental implants. To enhance bioac-tivity on the surface, strontium(Sr) and sili-con(Si) ions can be added to PEO treated sur-face in the electrolyte containing these ions. The presence of Sr in the coating enhances osteoblast activity and differentiation, where-as it inhibits osteoclast production and prolif-eration. And Si has been found to be essen-tial for normal bone, cartilage growth, and development. In this study, electrochemical characteristics of Ca, P, Sr, and Si ions from PEO-treated Ti-6Al-4V alloy surface was re-searched using various experimental instruments. DC power is used and Ti-6Al-4V al-loy was subjected to a voltage of 280 V for 3 minutes in the electrolyte containing 5, 10, 20M% Sr ion and 5M% Si ion. The morphol-ogies of PEO-treated Ti-6Al-4V alloy by electrochemical anodization were examined by field-emission scanning electron micro-scopes (FE-SEM), energy dispersive x-ray spectroscopy (EDS), x-ray diffraction (XRD) and corrosion analysis using AC impedance and potentiodynamic polarization test in 0.9% NaCl solution at similar body tempera-ture using a potentiostat with a scan rate of 1.67mV/s and potential range from -1500mV to + 2000mV.

• Journal of Korean Physical Therapy Science
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• v.24 no.1
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• pp.38-48
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• 2017

Background: This study was carried out to find out general characteristics and health-related behaviors of elders aged 65 or over and factors related to their activities of daily living, and thus to contribute to their health maintenance and promotion. The subjects were 200 elders who had resided at Cheju city, with males and females was scaled 1 : 3. Methods: To collect data for study, the field survey was conducted from March 20 to October 31, 2016 with questionaire. Results: This study are as follows; 65.0% of the subjects were 65-75 years old, while 35.0% were 75years old or over, 20.5% of them were illterate, 46.5% could read and write Korean, graduated from elementary school, and 11.5% middle school or higher level. 28.5% of subjects perceived their current health status, 46.0% of men and 38.0% of women as fair, In general elderly men perceived their health status better than elderly women. Among the subjects, 62.0% of men and 57.0% of women reported that they experienced one or more illnesses during the last year. 76.0% of men and 33.0% of women were current smokers. 55.0% of current smokers. 55.0% of current make smokers smoked 11-12 cigarettes per day and 53.2% of current female smokers smoked less than 10 cigarettes per day. 76.0% of men and 37.3% of women drank alchol currently. 56.0% of men and 34.7% of women practiced regular exercise for their health maintenance and promotion. In general, 38.5% of subjects needed other's assistance for doing one or more Activites such as doing heavy home work, Walking up and down stairs or walking half a mile. Common disease of the subjects were hypertention, depenerative arthritis and diabetes mellitus in order. Conclusion: This study ADL activity are significant effect.

• The korean journal of orthodontics
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• v.15 no.1
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• pp.141-148
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• 1985

It has been a long time since the cephalometrics was introduced to orthodontic field for diagnosis and treatment planning, but it's main concern was limited to hard, skeletodental tissue. It is well known that perioral and facial soft tissue determine the position of individual teeth and that the abnormality in size and shape of the soft tissue are able to cause malformed occlusion. Because of our lack of knowledge about resultant morphologic changes in the relationship between skeletal pattern and specific pattern of lingual and facial muscles, we can't help setting greater value on only abnormalities of teeth in the skeletal interrelationship. In a point of view that the orthodontist is dealing primarily with muscular structures around the dentition, the tongue, lips, and cheeks, therefore it may be desirable to estimate these structure and their potential influence on the dentition on developmental and time base. The author hit upon on idea of the aspect above, so studied on the intermaxillary space and tongue space and this study used the data from cephalometric films of 33 male and 40 female subject aged from 6 to 11 years of normal Korean children following results were obtained: 1. Means and standard deviation of Korean children were obtained. 2. Yearly increment of each variables were obtained. 3. There is the correlationship more than average among the variables except posterior intermaxillary height item. 4. There are differences between male children and female children in all variables except posterior intermaxillary space item. 5. All variables increased as the age increased except posterior intermaxillary height item of male children.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1710-1715
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• 2010

Service life of water pipes buried in the underground is considerably affected from various factors such as environmental characteristics, pipe characteristics, operation and maintenance, etc. Therefore it is difficult to determine their service life as uniformly the same value assigned by related laws and ordinances. As a result, the service life should be determined by the technical judgement based on the assessment for the condition of water pipes. In this study, It was established that the methodology could predict present and future failure risk, and plan short and long-term strategies for replacement/rehabilitation through the assessment for the physical deterioration and economical values of buried water pipe. The methodology was applied for the verification and reliability to several sites selected in multi-regional transmission pipelines. The proposed method could helps to support reasonable and economical decision of rehabilitation/replacement in the present and future. To improve conventional assessment method of aged water pipes, affecting factors are simplified based on the statistical analysis results from the measured data in the field and the physical deterioration mechanism for better reliability. Also, the guide-line is developed to carry out the reasonal rehabilitation planning through water pipe condition assessment.

• Journal of Sensor Science and Technology
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• v.10 no.1
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• pp.33-41
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• 2001

Wire ropes have been widely used in industrial applications, wherever heavy weight should be carried safely or mechanical energy should be transmitted fast. Especially, wire rope failures in operating elevator may lead to extensive property damage and serious injury to nearby personnel. Hence, it is very important to inspect wire rope periodically. Failure defection of wire rope requires fundamental knowledge of wire rope construction, rope behavior, properties of fault, sensing and signal processing method. In this research, the development of a new fault detecting system incorporating Hall-effect sensors to detect flaws such as abrasion, broken wire, corrosion and deformation for aged wire ropes in elevator, is described. For using a detector as a portable instrument, several performances for implementing sensing part with Hall-effect sensor, analog signal processing unit and programs are described. Experiments and field testing results for the implemented detecting system are also given. As a result, it is verified that the detecting system has good efficiency for inspecting faults of aged wire ropes in service.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.1
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• pp.91-109
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• 2014

This study was conducted to obtain the basic research about Siberian roe deer (Capreolus pygargus), and to establish a conservation area into Seoraksan(Mt.) National Park, South Korea. We recorded Siberian roe deer field signs (bedding sites, feeding areas, feces and tracks etc), and habitat variables such as nearest distance to the watercourse, trails, slope, aspect, forest type and land cover etc. from Jan. 2006 to Dec. 2007 in Seoraksan(Mt.) National Park. According to the research of habitat characteristics of Siberian roe deer inhabited in Seoraksan(Mt.) National Park preferred mixed forest consisted of aged forest and middle-aged forest on the gentle slope which was close to hydrosphere in the middle elevation area of altitude of 400~600m above sea level in Seoraksan(Mt.) National Park. The results indicated that Siberian roe deer appeared to prefer south slope or north slope during the snow season and west or east slope during the non-snow season. The area of most suitable habitat for Siberian roe deer in Seoraksan(Mt.) National Park was $128.5km^2$ (32% of the total area) followed by $244.3km^2$ buffer area (62.2% of the total area), and $22.9km^2$ unsuitable habitat area (5.8% of the total area), which means environmentally unsuitable habitat for Siberian roe deer was rare in Seoraksan(Mt.) National Park. Thus, the area classified as major area in Seoraksan(Mt.) National Park appeared to be most important for the protection of Siberian roe deer.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.4
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• pp.329-336
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• 2021

Background: In the field of dentistry, topical anesthetics play an important role in reducing pain during needle pricks. The anesthetic property of betel leaves remain unexplored, even though they have been widely used for the treatment of various ailments. The purpose of this study was to compare and evaluate pain perception following topical application of lignocaine gel, clove gel, ice, and newly developed betel leaf extract gel during intraoral injection in children. Methods: Sixty children aged 6-10 years who met the inclusion criteria were divided into four groups. Topical anesthetic agents, 2% lignocaine (Lox-2% Jelly, Neon, Mumbai, India), 4.7% clove gel (Pain Out Dental Gel, Colgate Palmolive India Ltd, Solan, India), 10% betel leaf extract gel, and ice were applied to each group for one min, followed by administration of infiltration anesthesia. Pain perception was analyzed during needle insertion. The Wong Bakers FACES pain rating scale (WBFPRS) was used for subjective assessment and the Sound, Eye, Motor (SEM) scale for objective assessment. Recorded values were tabulated and subjected to appropriate statistical analysis using SPSS software with a P value set at 0.05. Results: The clove oil and betel leaf groups demonstrated the highest WBFPRS scores, followed by the ice and lignocaine groups. The clove, betel leaf extract, and ice groups showed equal and highest SEM scores, followed by the lignocaine group. The mean WBFPRS and mean SEM scores were statistically significant. Conclusion: Betel leaf extract gel is effective in reducing pain and can act as an alternative topical anesthetic agent.

• Journal of People, Plants, and Environment
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• v.22 no.6
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• pp.699-709
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• 2019

Various health and social issues related to the elderly are emerging in line with the rapid aging of the population. In particular, dementia currently has a prevalence of about 10 percent of the elderly population in South Korea, which increases financial and social burdens to not only individual patients but also their caring family. To assess the effects of participating in the forest therapy programs for dementia prevention, this study recruited participants aged 50 and above and tested their depression (Korean form of Geriatric Depression Scale; KGDS) and stress response (Modified form of Stress Response Inventory; SRI-MF), which are emotional aspects of dementia. As a result, KGDS showed a significant decrease of 3.2 points from 8.4 to 5.2 points, and SRI-MF showed a significant decrease of 7.2 points from 40 to 32.8 points, indicating a statistically significant improvement in both. In addition, participants with minor depression and high level of stress in the pretest showed statistically significant improvements in the SRI-MF for men, and the KGDS and SRI-MF for women. Furthermore, there were statistically significant improvements in KGDS for participants in their 60s and in SRI-MF for those in their 70s in terms of age, and in both KGDS and SRI-MF for participants with chronic diseases and in KGDS for participants without chronic diseases. This study confirmed the effects of forest therapy on the prevention of the emotional aspects of dementia and laid the groundwork for increasing the applicability of forest therapy by obtaining a place for dementia prevention as a field of forest therapy.

• Pediatric Infection and Vaccine
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• v.19 no.3
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• pp.149-156
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• 2012

Purpose : We conducted a prospective comparative clinical study to determine the field efficacy of the 2010-2011 influenza vaccines [Influenza virus strains; A/California/7/2009 (H1N1), A/Perth/16/2009 (H3N2), B/Brisbane/60/2008] in healthy Korean children under 18 years of age. Methods : In this study, we enrolled subjects aged between 6 months and 18 years and divided them into 2 study groups: a group who received the influenza vaccines (407 subjects), and a control group who did not receive the influenza vaccines (230 subjects). Ours was a multicenter study that involved 7 hospitals, including the Korea Cancer Center Hospital. The study was conducted between September 2010 and February 2011. We collected nasal wash or throat swab samples from subjects who presented with acute febrile respiratory or influenza-like illnesses at the hospital. We used PCR to confirm the presence of the influenza virus in the respiratory samples and characterize the virus type. Results : In this study, we collected 22 respiratory samples from the influenza-vaccinated group and found 3 cases of influenza virus infection. Similarly, we collected 21 samples from the control group and found 12 cases of influenza virus infection among 10 subjects during the study period. We determined the field efficacy of the 2010-2011 seasonal influenza vaccines to be 83.2% in healthy Korean children and adolescents. Conclusion : In this study, we determined the field efficacy of the 2010-2011 seasonal influenza vaccines in healthy Korean children and adolescents. We found that the field efficacy of 2010-2011 seasonal influenza vaccines was adequate.