• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.538-547
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• 2022

In this study, the population and community structure of Berchemia berchemiaefolia stands located at Mt. Naeyon (Gyeongbuk, Korea) were quantified, and multivariate analysis was done to determine the correlations between vegetation group types and environmental factors and to have reference data for the conservation and restoration of this species. In total, there were 164 B. berchemiaefolia trees in Mt. Naeyon. The average DBH of the trees was 24.5 cm, forming a normal distribution. It rarely appeared in an understory vegetation height of 3 m. About37.1% of the trees were branched. B. berchemiaefolia stands were classified into two groups: B. berchemiaefolia-Quercus serrata community and B. berchemiaefolia-Carpinus laxiflora community. Canopy gap, organic matter, exchangeable Ca, and cation exchange capacity were the major site characteristics affecting the distribution pattern of the stands. Currently, B. berchemiaefolia trees dominate in Mt. Naeyon, but depending on different habitat positions, the species was in a natural successional stage to C. laxiflora or C. cordata, which is a shade-tolerant species.

• Journal of Wetlands Research
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• v.19 no.2
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• pp.193-201
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• 2017

This study was carried out to obtain basic ecological information required for wetland restoration in Korea where wetland is very deficient. To arrive at the objective, we collected the basic ecological information for wetland restoration in four Doombeongs located on Goesan of Chungcheongbuk-do (province), central Korea where maintains relatively integrate feature of Doombeong. Synthesized horizontal distribution of vegetation based on vegetation established naturally except that established by artificial interference, Potamogeton distinctus community, Spirodela polyrhiza community, Sagittaria aginashi community, Trapa japonica community, Scirpus triangulatus community, and Sparganium japonicum community, Persicaria thunbergii community, Juncus effusus var. decipiens community, Ludwigia prostrata community, Humulus japonicus community, Persicaria nodosa community, Miscanthus sacchariflorus community, Phragmites communis - P. japonica community, and Scirpus radicans community, S. gracilistyla community, Spiraea prunifolia for. simpliciflora community, and Rosa multiflora community, and Salix koreensis community and Acer tataricum subsp. ginnala community tended to be established in aquatic zone, herbaceous plant dominated vegetation zone, shrub dominated vegetation zone, and tree and sub-tree dominated vegetation zone, respectively. As the result of DCA ordination based on vegetation data collected from several Doombeongs and their surrounding areas, plant communities tended to be classified into aquatic, wetland, and riparian plant dominated stands. Spatial niche and species composition of major plant communities composing those stands were suggested as the reference information for creating ecological pond as a type of wetland. Further, the importance of wetland and the necessity of wetland restoration was discussed based on functions that the wetland displays.

• Imaging Science in Dentistry
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• v.46 no.3
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• pp.185-202
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• 2016

Purpose: The goal of this study was to develop a new index as an objective reference for evaluating current and newly developed indices used for osteoporosis screening based on dental images. Its name; IDIOS, stands for Index of Dental-imaging Indices of Osteoporosis Screening. Materials and Methods: A comprehensive PubMed search was conducted to retrieve studies on dental imaging-based indices for osteoporosis screening. The results of the eligible studies, along with other relevant criteria, were used to develop IDIOS, which has scores ranging from 0 (0%) to 15 (100%). The indices presented in the studies we included were then evaluated using IDIOS. Results: The 104 studies that were included utilized 24, 4, and 9 indices derived from panoramic, periapical, and computed tomographic/cone-beam computed tomographic techniques, respectively. The IDIOS scores for these indices ranged from 0 (0%) to 11.75 (78.32%). Conclusion: IDIOS is a valuable reference index that facilitates the evaluation of other dental imaging-based osteoporosis screening indices. Furthermore, IDIOS can be utilized to evaluate the accuracy of newly developed indices.

• The Journal of Information Technology and Database
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• v.7 no.1
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• pp.42-53
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• 2000

The major goal of this research is to develop an optimal route search algorithm for an intelligent route guidance system, one sub-area of ITS. ITS stands for intelligent Transportation System. ITS offers a fundamental solution to various issues concerning transportation and it will eventually help comfortable and swift moves of drivers by receiving and transmitting information on humans, roads and automobiles. Genetic algorithm, and fuzzy logic are utilized in order to implement the proposed algorithm. Using genetic algorithm, the proposed algorithm searches shortest routes in terms of travel time in consideration of stochastic traffic volume, diverse turn constraints, etc. Then using fuzzy logic, it selects driver-preference optimal route among the candidate routes searched by GA, taking into account various driver's preferences such as difficulty degree of driving and surrounding scenery of road, etc. In order to evaluate this algorithm, a virtual road-traffic network DB with various road attributes is simulated, where the suggested algorithm promptly produces the best route for a driver with reference to his or her preferences.

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.683-691
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• 2001

This study aimed to clarify the influencing factors of the mesopore ratio on a pore geometry of surface soil in mixed stands as an index of the water retention capacity. Twenty four factors including site conditions and soil properties were analyzed by spss/pc+ for the data collected from during March to October of 1995. The factors influencing the mesopore ratio(pF2.7) on the surface soil were as follows; mesopore ratio(pF2.7) on the B horizon soil, under vegetation coverage, organic matter contents of surface soil and F layer depth. And influencing factor on the ratio of mesopore in the soil surface was correlated with surface soil hardness and depth of 10cm soil hardness shows high negative significance. Also, multiple regression equations for mesopore ratio of the mesopore ratio of B horizon soil and organic matter contents shows high significance($R^2$; 0.84).

• Journal of Korean Society of Forest Science
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• v.108 no.3
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• pp.349-356
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• 2019

This study examines the effect of thinning in terms of changes in the growth characteristics of Chamaecyparis obtusa stands after they were thinned with varying intensity in Gochang, North Jeolla Province, Korea. Thinning was carried out in 2000 on Chamaecyparis obtusa stands (22 years old), and the stands were categorized in terms of the thinning intensity in the experiment: very heavy, heavy, medium, light, and control. The results of monitoring up to 2018 revealed that the diameter at breast height and the growth rate of individual trees after thinning had a positive correlation with the thinning intensity, whereas the stand volume showed a negative correlation. The height to diameter (H/D) ratio decreased by up to 70-80 due to the increased diameter at breast height after thinning and thereby resulted in better quality. The relative yield index right after the first thinning was between 0.75 and 0.95, which suggests the best timing for the first thinning had been missed. This study's findings are expected to serve as a basic reference in establishing the thinning system for Chamaecyparis obtusa forests.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.11 no.2
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• pp.35-41
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• 1993

The height differences in Mean Sea Level is an important factor in geodetic leveling net, because MSL is the reference datum for height. Geodesists and Oceanographers agree on the height differences in MSL in the east-west direction, but they disagree almost always on the north-south slope, each suspecting systematic errors in the leveling methods of the others. A promising method for determining this slope is comparison of MSL at the tidal station connected by geodetic leveling. The slopes of the sea surface along the coast of Korean Peninsular is estimated from conventional local MSL at the tidal station and bench mark height of first order leveling net in Korea. As a reference level surface, MSL at Inchon is chosen. The results indicate that sea level rises along coast of Korean Peninsular from south to north about 5.5 cm/latitude. In the east-west direction, sea level along East Sea coast stands about 5 cm higher than that along Yellow Sea coast. These are not invariable but provisional phenomena. It may become certain provided that the exact MSL is estimated.

• Safety and Health at Work
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• v.4 no.2
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• pp.117-121
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• 2013

This paper describes progress on formulating a national asbestos profile for the country of Vietnam. The Center of Asbestos Resource, Vietnam, formulated a National Profile on Asbestos-related Occupational Health, with due reference to the International Labor Organization/World Health Organization National Asbestos Profile. The Center of Asbestos Resource was established by the Vietnamese Health Environment Management Agency and the National Institute of Labor Protection, with the support of the Australian Agency for International Development, as a coordinating point for asbestos-related issues in Vietnam. Under the National Profile on Asbestos-related Occupational Health framework, the Center of Asbestos Resource succeeded in compiling relevant information for 15 of the 18 designated items outlined in the International Labor Organization/World Health Organization National Asbestos Profile, some overlaps of the information items notwithstanding. Today, Vietnam continues to import and use an average of more than 60,000 metric tons of raw asbestos per year. Information on asbestos-related diseases is limited, but the country has begun to diagnose mesothelioma cases, with the technical cooperation of Japan. As it stands, the National Profile on Asbestos-related Occupational Health needs further work and updating. However, we envisage that the National Profile on Asbestos-related Occupational Health will ultimately facilitate the smooth transition to an asbestos-free Vietnam.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.1
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• pp.101-106
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• 2014

PURPOSE: This study was to provide reference data and examine stroke and healty older differences in sit-to-stand test. This study were to determine utility of the 5 repetition sit to stand for discriminating between fallers and non-fallers, identifying an appropriate cutoff score to delineate between the groups. METHODS: Ninety-five participants were recruited. Seventy-two individuals with stroke and twenty-three healthy older agreed to participate in the study. Falls were recorded using a self-administered questionnaire. The 5 repetition sit to stand test measured the time taken to complete t repetitions of the sit to stand maneuver. The time from the initial seated position to the final seated position after completing five stands was the test measure. A cutoff score regarding 5 repetition sit to stand performance in fallers vs. non-fallers, stroke patients vs. healthy older and <60 vs. $$\geq_-$$ age groups was determined using and ROC curve. RESULTS: Cutoff score of 9.9 seconds were found to be discriminatory between healthy older and subjects with stroke. Cutoff score of 15.5 seconds were found to be discriminatory between fallers and non-fallers. Cutoff score of 18.3 seconds were found to be discriminatory between <60 and $$\geq_-$$ age groups. CONCLUSION: The 5-repetition sit-to stand test is quick, easily administered measure useful for gross determination of fall risk in people with stroke.

• Proceedings of the KIEE Conference
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• 1999.11c
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• pp.561-563
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• 1999

The looper of a hot strip finishing mill is installed between each pair of stands and plays a key role to enhance the product quality of strip by controlling the tension and height of strip in each inter-stand. Though the conventional looper control has achieved the mass products of strip so far, it has difficulties not only tuning gains by means of errors which are caused by coupling effects between strip tension and looper angle both utilizing tension feedback. Therefore, the non-interactive control employing cross controller and tension feedback has been introduced in looper control system in order to overcome the coupling effects existing between tension and looper angle and track the reference tension efficiently. In this paper, we present the cross controllers which play a role to decouple reciprocal effects between tension and looper angle and show better performance.