• Journal of Korean Dental Science
• /
• v.14 no.2
• /
• pp.61-68
• /
• 2021

Purpose: The aim of this study was to investigate the outcomes of endodontic treatment of mandibular second molar with C-shaped canal in elderly patients and related factors affecting the survival of the tooth. Materials and Methods: From 2010 to 2015, the survival rate following endodontic treatment was evaluated in elderly patients over 60 years who visited the Veterans Health Service Medical Center for endodontic treatment. The presence of C-shaped canals was confirmed using clinical records and radiographic features. Patient's age, sex, systemic diseases, tooth location, vitality, signs and symptoms, fractures, caries, apical radiolucency, canal shaping methods, sealer leakage, filling voids, and restoration of prosthesis were included in the analyses as confounding variables. The survival rate of teeth was analyzed using Kaplan-Meire analysis and the relationship between the survival rate and variables was analyzed using Simple and Multiple Cox regression analysis. Result: In total, 107 teeth in elderly patients had C-shaped canal. The survival rate of teeth that received endodontic treatment was 63.70%. None of the factors investigated significantly influenced the survival rate (P>0.05). Conclusion: In elderly patients with C-shaped canal, the survival rate after root canal treatment was not significantly different from that of other mandibular molars.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.12 no.6
• /
• pp.112-122
• /
• 2009

Payment of Forest Landscape Service (PFLS) is based on the value of landscape conservation and is a positive forest policy inducing the owners of mountains to improve environmental service quality with economic incentives. The purpose of this study is to test the feasibility of PFLS and find out the elements related to PFLS such as associated statutes, target applications, eligible owner's requirements, and applicable environmental services. Research sites were selected in designated reserved forests by law and surveys were carried out with 28 professional forestry engineers and 10 owners of reserved forests located in Chungnam Province in November, 2008. As a result, the owners are willing to participate pilot-project of PFLS if they could have tax incentives. Preferred activities in their forestry are eco-tourism and carbon emission trading as PFLS business model. Although they expect low economic benefit from the PFLS, respondents answered introducing PFLS will give good opportunities for owners of a reserved forest to enhance willingness to manage their forestry properly for the landscape conservation. In this study, PFLS evaluation indicators and policy directions are established and recommends the strategies to cope with changing needs of forestry conservation by inducing the owners' active participation in the sustainable forest landscape management.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.26 no.6
• /
• pp.97-115
• /
• 2023

Ecosystem services (ES) are the benefits that people obtain from ecosystems. Traditional ES assessment methods have focused on the supply of ES, using biophysical data. However, these methods often fail to capture the full value of ES, which is also determined by social and cultural factors. This study proposes a new approach to ES assessment that incorporates socio-cultural perspectives. The study was conducted in Seoul, South Korea. A survey was conducted of 1,805 residents of Seoul to assess their satisfaction with ecosystem services. Exploratory factor analysis was used to identify bundles of ES that were perceived as important by residents. A revised importance-satisfaction analysis was used to calculate the urgency level of each bundle. The results of the study showed that the 21 ES that were considered in the survey could be grouped into three bundles: urban green area-based, biodiversity-based, and resilience-based. The urgency level analysis showed that some bundles were more important than others, and that some bundles were more urgent than others. The findings of this study have several implications. First, they suggest that a socio-cultural approach to ES assessment can provide a more comprehensive and accurate assessment of ES. Second, they show that this approach can be used to identify areas where ES management is most needed. Third, they suggest that this approach could be used to inform ES management and policy decisions.

• Proceedings of the IEEK Conference
• /
• 2005.11a
• /
• pp.237-240
• /
• 2005

We propose a fully converged Ethernet and TDM transport system. Developed Ethernet and TDM convergence system can support not only L2VPN service and premium multimedia service based on MPLS protocol but also TDM leased line service, simultaneously. Developed convergence system can provide high reliability for Ethernet data due to support protection and restoration function of circuit based networks. Evaluation for Ethernet and TDM path was successfully performed to show the typical application of the proposed system in the legacy networks.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.12 no.1
• /
• pp.13-31
• /
• 2009

The objectives of this study were to offer the basic data for the restoration and conservation of forest wetland by surveying systematically the vascular plants of Sandeul wetland in Mt. Jaeyak, Miryang-si, Gyeongsangnam-do, Korea. The vascular plants in this wetland were recorded as 232 taxa; 74 families, 178 genera, 200 species, 27 varieties and 5 forma. The major communities were Quercus mongolica, Tripterygium regelii, Alnus japonica, Molinia japonica, Salix gracilistyla and Stephanandra incisa. The numbers of plant species by routes were 168 taxa in A-route, 126 taxa in B and 132 taxa in C. The ecological problems in Sandeul wetland were the afforestation of Pinus koraiensis and P. thunbergii, the appearance of naturalized plants, the invasion of species and the scour of valley. The Korean endemic plants were 5 taxa; Salix hallaisanensis, Hepatica insularia; Chrysosplenium barbatum, Ajuga spectabilis and Weigela subsessilis. The rare plants designated by Korea Forest Service were 3 taxa; Aristolochia manshuriensis, Chrysanthemum lineare and Iris ensata var, spontanea. The naturalized plants were 8 taxa; Rumex acetocella, R. crispus, Trifolium repens, Oenothera lamarckiana, Ambrosia artemisifolia var. elatior, Helianthus tuberosus, Erigeron annuus and Phleuum pratense.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.46 no.2
• /
• pp.1-9
• /
• 2009

In recent years, a film restoration has gained increasing attention by many researchers, to support multimedia service of high quality. In general, an old film is degraded by dust, scratch, flick, and so on. Among these, the common factors are scratch and blotch, so that many researchers have been investigated to restore these degradations. However, the methods in literature have one major limitation: A method is working well in dealing with scratches, however it is poorly working in processing the blotches. The goal of this work is to develop a robust technique to restore images degraded by both scratches and blotches. For this, we use MRF-MAP (Markov random field - maximum a posteriori) framework, so that the restoration problem is considered as the minimization problem of the posteriori energy function. As the minimization is one of complex combinatorial problem, we use distributed genetic algorithms (DGAs) that effectively deal with combinatorial problems. To asses the validity of the proposed method, it was tested on natural old films and artificially degraded films, and the results were compared with other methods. Then, the results show that the proposed method is superior to other methods.

• Restorative Dentistry and Endodontics
• /
• v.49 no.3
• /
• pp.24.1-24.13
• /
• 2024

Objectives: This study aimed to evaluate the clinical performance of an alkasite restorative material in molars that had undergone root canal treatment. Materials and Methods: The research was registered in Brazilian Registry of Clinical Trials. The randomized clinical trial involved 33 patients, each with at least 1 mandibular molar requiring restoration after receiving endodontic treatment. Patients were randomly assigned to receive either bulk-fill resin composite (Tetric N Ceram Bulk Fill, Ivoclar Vivadent) or the alkasite restorative material (Cention N, Ivoclar Vivadent). Upon completion of the restorations, 3 calibrated professionals utilized the United States Public Health Service criteria to assess various factors, including retention, secondary caries, marginal adaptation, restoration color, marginal pigmentation, and anatomical form. Evaluations were conducted at intervals of 7 days, 6 months, and 17 months. Additionally, the assessment encompassed the presence of radiolucent lines adjacent to the restoration, material deficiencies or excess, contact points, and caries recurrence. The data underwent analysis using the Friedman and Mann-Whitney tests (α = 0.05). Results: After 17 months, the results revealed that the alkasite restorative material exhibited greater wear of anatomical shape compared to the bulk-fill resin composite (p = 0.0189). Furthermore, the alkasite restorative material significantly differed from the natural tooth color in most cases (p = 0.0000). However, no other criteria displayed significant differences between the materials or over time (p > 0.05). Conclusions: The alkasite restorative material (Cention N) emerges as a viable option for restoring endodontically treated teeth, displaying clinically acceptable alterations after a 17-month evaluation period.

• Korean Journal of Environment and Ecology
• /
• v.36 no.5
• /
• pp.481-495
• /
• 2022

This study was designed to identify the actual state of naturalized plants and invasive alien species that cause disturbances to the ecosystem, plants which are introduced after forest restoration, and explore the implications resulting from the project. Onsite examination included 29 sites which have been subjected to forest restoration by the Korea Forest Service. Once these were chosen, activity took place twice a year in the spring (May-June) and in the summer (August-September) in 2020 and 2021. Areas not relevant to the project sites were excluded from this activity so that we could identify the plants that could be understood to have been introduced or brought into the site after the actual forest restoration. And the correlation was analyzed, between the naturalized flora within the project sites and the working types applied to the site through confirmation of completion of the restoration project. The naturalized plants appearing on the entire site cover a total of 109 taxa, which includes 29 families, 80 genera, 108 species and 1 subspecies, while invasive plants included 3 families, 7 genera and 8 species. The number of classifications and the naturalization rate gradually decreased over time, after the project. While there was no significant difference between the number of classification groups and the naturalization rate for naturalized plants between project sites, given the number of taxa of naturalized plants, organized by type of damage, there were relatively more naturalized plants that appeared in the severed section of the Baekdudaegan Mountain Range, as well as at quarry and facility sites. Seeding apparently results in naturalization rates as high as 15.545%, on average, based on comparisons of naturalization rates by sowing, seeding, planting, herb planting, and sod pitching channels, all of these being methods of vegetation for planting/greening of bareland and slopes within the project areas. With no seeding, it was 9.167%, higher than the average. As for other vegetation, there was no significant difference depending on application of the working type. This means that unlike the plants subjected to planting, the working type of seed planting which makes it difficult to identify whether a certain plant is a naturalized plant greatly affects the introduction of naturalized plants to the restoration sites, even when using herb planting and sod pitching to control plants and results. Therefore the study suggests that there be inspection by experts of seeds when sowing within restoration sites. The results of this study suggest good practices that will help to direct effective vegetation restoration and follow-up management.

• The Journal of Korean Academy of Prosthodontics
• /
• v.62 no.2
• /
• pp.113-122
• /
• 2024

The gradual teeth wear with age is a natural phenomenon, but excessive wear beyond physiological levels can lead to vertical dimension loss, occlusal imbalance, temporomandibular joint disorders, and periodontal disease. In such cases, prosthodontic restoration becomes necessary emphasizing the importance of appropriate vertical dimension increase and stable occlusion in central relation (CR). In this case, a 74-year-old patient with clenching and grinding habit had severe teeth wear and after assessing interocclusal distance, wear degree, pronunciation, and facial profile, it was decided to perform full-mouth fixed prosthesis restoration with a 4 mm vertical dimension increase. And the significantly displaced Maximum Intercuspal Position (MICP) caused by parafunctional movements was re-established as a stable mutually protective occlusal relationship at centric relation and after a successful 4 months adaptation to provisional restorations, the final prosthesis was fabricated. During 4months of observation periods, stable occlusion in central relation and mutual protection occlusal relationships were maintained and the patient was satisfied with function and aesthetics, leading to this report.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.18 no.1
• /
• pp.135-146
• /
• 2015

This study was carried out to understand ecological characteristics of Korean goral such as home range, seasonal home range and habitat use and used for Korean goral restoration and conservation, through a pair of gorals in the north Gyeongbuk province of Korea. With data from GPS collars, we analyzed the behavioral characteristics of the endangered Korean gorals(n=2) in Uljin area from June 2013 to July 2014. As a result, their home range was $1.38{\pm}0.24km^2$ in MCP 95%, $0.81{\pm}0.09km^2$ in FK 95% and $0.15{\pm}0.16km^2$ in FK 50% (t=8.118, p>0.05). Seasonal home range for MCP 95% was $0.74{\pm}0.31km^2$ > (winter) > $0.71{\pm}0.27km^2$ (spring) > $0.61{\pm}0.06km^2$ (autumn) > $0.27{\pm}0.04km^2$ (summer) (F=2.135 p>0.05). It showed that home range in winter was the largest and that in summer was the smallest. Mean elevation of male for seasonal habitat use was $440.18{\pm}71.32m$ in summer and that of female was $727.25{\pm}99.98m$ in spring. The lowest altitude for male was $372.72{\pm}70.79$ and female was $664.60{\pm}139.71m$. It meant that there were seasonal change and thus annual and seasonal behavior characteristics for both sexes had different correlation according to elevation change. Although in this study the correlation with prey in habitat and the changes of habitat disturbance were not clearly investigated, We could understand goral home range and habitat use through research data.