• Economic and Environmental Geology
• /
• v.52 no.3
• /
• pp.223-230
• /
• 2019

The calcination of oyster shells have been studied as the possible substitute for the limestone used as an absorbent of $SO_2$ gas. However, since pure shells can not be used in calcination process, some impurities are contained and the changes in the characteristics of the calcination products are expected. In this study, the surface characteristics of the calcination products are investigated by mineralogical analysis according to the contents of NaCl, which can be derived from sea water, and sediments on the surface of the shell as impurities. The marine sediments on the shells were mainly composed of quartz, albite, calcite, small amounts of amphibole and clay minerals such as ilite, chlorite and smectite. After calcination of oyster shells mixed with 0.2-4.0 wt% sediments at $900^{\circ}C$ for 2 hours, regardless of the dehydration, dehydroxylation, and phase change of these minerals at the lower temperature than this experiment, no noticeable changes were observed on the specific surface area of the calcined product. However, when mixed with 0.1 to 2.0 wt% NaCl, the specific surface area generally increases as compared with the shell sample before calcination. The specific surface area increases with increasing amount of salt, and then decreases again. This is closely related to the changes of surface morphology. As the amount of NaCl increases, the morphology of the surface is similar to that of gel. It changes into a slightly angular, smaller particle and again looks like gel with increasing amount of NaCl. Our results show that NaCl affects morphological changes probably caused by melting of some oyster shells, but may have different effects on the specific surface area of calcination product depending on the NaCl contents.

• Journal of Nutrition and Health
• /
• v.52 no.1
• /
• pp.104-117
• /
• 2019

Purpose: This study examined dietary and health characteristics of the young-old and the old-old by food security status. Methods: The study used data from the $6^{th}$ (2013 ~ 2015) Korea National Health and Nutrition Examination Survey. The study subjects consisted of 3,948 subjects, of whom 2,445 were the young-old (aged 65 to 74 years) and 1,503 were the old-old (aged 75 years and over). Food security status was evaluated using an 18-item questionnaire. Energy intake, nutrient densities, and prevalence of insufficient nutrient intake were assessed. Food intake was evaluated in terms of the number of food group servings. Dietary behaviors and health status were also assessed. Results: The prevalence of food insecurity among the young-old and the old-old was 10.0% and 11.6%, respectively. Among the young-old, the food insecure group had a significantly higher level of prevalence of insufficient intake for all the nutrients (protein, vitamin A, thiamin, riboflavin, niacin, vitamin C, calcium, phosphorous, and iron) assessed in this study compared with the food secure group. In case of the old-old, significant differences were found only for four nutrients (protein, riboflavin, niacin, and phosphorus) in the prevalence of insufficient nutrient intake between the food secure and the food insecure groups. Kinds of food groups with significantly different numbers of servings by food security status were dissimilar between the two age groups. In both the age groups, the food insecure group consumed a significantly lower number of servings in meat fish eggs legumes and fruits than the food secure group; grains and vegetables intake in the young-old and oils sweets intake in the old-old differed in the number of servings by food security status. Among the young-old, the prevalence of chewing difficulties in the food insecure group was significantly higher than that of the food secure group, while among the old-old, no significant differences were found by food security status. Conclusion: Dietary and health characteristics of the young-old and the old-old differed by food security status. Such differences were more apparent in the young-old than the old-old. Therefore, it is suggested that food and nutrition assistant programs should be designed with consideration of the differences.

• Journal of Korean Society of Forest Science
• /
• v.100 no.4
• /
• pp.577-584
• /
• 2011

To estimate level of genetic variation and genetic differentiation among populations of 3 populations in Abies koreana and 5 populations in Abies nephrolepis, 5 nSSR markers were analyzed. Except 1 locus where too many alleles were observed excessively, population genetic parameters were recalculated with 4 loci. Mean expected heterozygosities ($H_e$) were 0.292 in A. koreana and 0.220 in A. nephrolepis, respectively. In both species, positive fixation coefficient was estimated (F=0.065 for A. koreana and F=0.095 for A. nephrolepis), which suggests that there is an excess of homozygotes relative to Hardy-Weinberg expectations within populations. Relatively high degree of population differentiation was observed in A. koreana ($F_{ST}=0.063$). compared to that of A. nephrolepis ($F_{ST}=0.039$). From 3-level Hierarchical estimation of F-staticstics, only 4.9% of the genetic variation was allocated between species ($F_{PT}$), which suggested that most of genetic variation was shared between two species. On the basis of results from analysis of genetic relationships among populations, 2 populations of A. koreana (Mt. Halla and Mt. Deogyu) were genetically distinct from the populations of A. nephrolepis but a population of Mt. Jiri was allocated within a group of populations of A. nephrolepis. Populations of both species seemed to have undergone genetic drift due to gradual decrease in population size induced by global warming after the last glacier, which resulted in increase of homozygotes by inbreeding. It could be also postulated that these species might be diverged recently and It is likely that the two species have not fully speciated yet.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.38 no.4
• /
• pp.12-24
• /
• 2020

The purpose of this study is to analyze the influence of the water system on the location, spatial structure, and construction method of Hongju-eupseong, centering on Hongjumok-eupchi. During the Joseon Dynasty, the water system in Hongjumok-eupchi is composed of artificially constructed Seong-an Runnel and ponds based on a branch-shaped natural waterways flowing from south to north and west to east. Compiling the results of various literature records, excavations and analysis of map data, it can be seen that the water system has an important influence on the construction of Hongju-seong. Firstly, Hongju-seong from the Goryeo Dynasty to the late Joseon Dynasty is located using a circular shape of topographical structure and a small erosion basin formed on the inner side of the Hongseongcheon and Wolgyecheon streams without significant change in location. In particular, Wolgyecheon and Hongseongcheon are natural moats, which are harmonized with Sohyangcheon and riverside topographical structures, affecting the location and construction method of Hongju-seong, water related facilities, and the spatial structure of eupseong. It is understood that location characteristic of Hongju-seong reflects the urban location structure harmonized with waterways in ancient China and Korea. Secondly in harmony with the water system and topographic structure of Hongju-seong, it is an important factor in deciding the land use of the town, the arrangement of the town hall facilities and inducing various non-subsidiary measures such as the establishment of embankment forest with a secret function and the closure of the south gate. In addition, artificial drainage facilities such as Seongan runnel and ponds are being actively introduced from early on to protect the walls or towns from flooding of Wolgyecheon. Especially there were typical methods for protecting the walls from water damage such as the Joseon Dynasty stone castle structure that was integrated with saturn(soil wall) in the Goryeo Dynasty, retreating wall in the northern gate area in the late Joseon Dynasty, and the method of constructing wall using korean tile and stone floors between reinforced soil layers in the western and northern wall.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.24 no.2
• /
• pp.12-28
• /
• 2021

Based on the global smart city promotion trend, in 2018, the "Fourth Industrial Revolution Committee" selected "sustainability" and "people-centered" as keywords in relation to the direction of domestic smart city policy. Accordingly, the Living Lab program, which is an active citizen-centered innovation methodology, is applied to each stage of the domestic smart city construction project. Through the Living Lab program, and in collaboration with the public and experts, the smart city discovers local issues as it focuses on citizens, devises solutions to sustainable urban problems, and formulates a regional development plan that reflects the needs of citizens. However, compared to citizen participation in urban regeneration projects that have been operated for a relatively long time, participation in smart city projects was found to significantly differ in level and sustainability. Therefore, this study conducted a comparative analysis of the characteristics of citizen participation at each stage of an urban regeneration project and, based on Arnstein's "Participation Ladder" model, examined the level of citizen participation activities in the Living Lab program carried out in a smart city commercial area from 2018 to 2019. The results indicated that citizen participation activities in the Living Lab conducted in the smart city project had a great influence on selecting smart city services, which fit the needs of local residents, and on determining the technological level of services appropriate to the region based on a relatively high level of authority, such as selection of smart city services or composition of solutions. However, most of the citizen participation activities were halted after the project's completion due to the one-off recruitment of citizen participation groups for the smart city construction project only. On the other hand, citizens' participation activities in the field of urban regeneration were focused on local communities, and continuous operation and management measures were being drawn from the project planning stage to the operation stage after the project was completed. This study presented a plan to revitalize citizen participation for the realization of a more sustainable smart city through a comparison of the characteristics and an examination of the level of citizen participation in such urban regeneration and smart city projects.

• Journal of Plant Biotechnology
• /
• v.49 no.2
• /
• pp.118-123
• /
• 2022

To obtain information on the molecular mechanism underlying the low temperature tolerance of sweet potato [Ipomoea batatas (L.) Lam], the proteome expressed in the sweet potato cultivar Xushu 15-1 with high cold storage tolerance and in the cultivar Xushu 15-4 with low cold storage tolerance was analyzed using 2-D and MALDI-TOF/TOF analyses. Compared with the control (without cold treatment), four protein spots were newly expressed in Xushu 15-1. The expression level of one protein spot was higher in Xushu 15-4 than in Xushu 15-1. Spot 2, which was newly expressed in Xushu 15-1, was identified as sporamin. Assessment of the change in protein expression levels over 8 weeks in the storage roots of the two cultivars treated at 4℃ revealed no significant difference in the expression levels in Xushu 15-1 over time. However, in Xushu 15-4, the expression level of one protein spot increased, while those of four spots decreased. Of the proteins with reduced expression levels, spots 7 and 8 were identified as actin and spots 9 and 10 were identified as fructokinase-like proteins. The present results are expected to enhance the understanding of the complex mechanism underlying the low temperature tolerance of sweet potatoes during storage and can be used to identify candidate genes for the development of new varieties of sweet potatoes with improved low temperature tolerance during cold storage in the future.

• Journal of the Korean Orthopaedic Association
• /
• v.56 no.3
• /
• pp.208-214
• /
• 2021

Purpose: Verifying a reliable predictor of the progression of vertebral deformity in patients with acute osteoporotic fractures of the lumbar spine may be useful. A qualitative analysis of the muscle near the spine was performed using magnetic resonance imaging (MRI), and its correlation with a spinal deformity was determined under the hypothesis that the causes of the kyphotic deformity are associated with muscle reduction in the multifidus and erector spinae. Materials and Methods: The study was performed in a retrospective manner using the electronic medical records of patients who presented to the author's institution between January 2007 and March 2018, and were diagnosed with an acute lumbar fracture. The fat infiltration rates of the multifidus and erector spinae were measured using MRI taken at the time of injury, and the mean value was defined as the total fat infiltration rate (TFI). Based on lateral radiographs of the lumbar spine at the one-year follow-up, the loss of height of the vertebral body, the kyphotic angle and the wedge angle were measured. The statistical significance was confirmed by calculating the Pearson correlation coefficient. Results: One hundred twenty-nine patients, of which 30 were male and 99 were female, were examined. The mean age was 71.28 years. The mean T-score was -3.53±0.79 g/cm², and the mean fat infiltration was 15.20%±11.99%. TFI was positively correlated with age (R=0.373, p<0.001), compression rate (R=0.369, p<0.001), and Cobb's angle (R=0.386, p<0.001) after a one year follow-up, but negatively correlated with the BMD score (R=-0.252, p=0.004). As the fracture progressed to the lower lumbar level, the compression rate (R=-0191, p=0.030) and wedge angle (R=-0.428, p<0.001) at the time of injury tended to decrease. Conclusion: In patients with osteoporotic vertebral fractures, the fat infiltration rate may be an important predictor of conservative treatment. The prognosis of patients with a high-fat infiltration rate should be explained during patient education, and the patients must be monitored closely through short-term outpatient follow-up.

• Journal of Korean Home Economics Education Association
• /
• v.34 no.1
• /
• pp.81-96
• /
• 2022

The purpose of this study was to examine the extent to which the contents of elementary and secondary curricula are connected and overlapped in the 'family life' area of Practical Arts(Technology & Home Economics) subjects. The procedure and results are as were like below. First, the types of criteria for analyzing curriculum contents are developed. The connectivity are classified as 'discontinuous hierarchy' and 'spiral hierarchy' and duplication are classified as 'repetition (high level of overlapping)', 'reproducing', 'deepening (intermediate level of overlapping)', 'substitution', and 'omission (low level of overlapping)'. Second, as a result of analyzing the contents of elementary and secondary curricula, the 'Human Development' area showed higher connectivity with a deepening type of duplication. The 'Safety' and the 'Lifelong Planning' concepts showed lower connectivity. Third, as a result of analyzing the achievement standards of the 2015 Curriculum, the secondary Home Economics curriculum showed a considerable increase in the level of difficulty and the volume compared to the elementary curriculum. There was low connectivity between the contents of elementary and secondary curricula in the core concepts 'Safety' and 'Lifelong Planning', an intermediate level of connectivity in 'Life Culture' and 'Management', and high connectivity in 'Development' and 'Relationship'. Also, there was a high level of duplication in the core concepts 'Safety' and 'Lifelong Planning', being classified as 'reproducing', 'substitution', and 'omission', analyzed to have low connectivity. When structuring the curriculum contents with a spiral hierarchy, one should connect the elementary and secondary school contents organically: the hierarchy with core concepts considering the different characters of constructuring knowledge in each school level, with a moderate volume, with a moderate difficulty level, with a moderate level of duplication of the contents, and with the minimum level of repetition of the same topics within the same school level.

• Journal of the Korean Society of Earth Science Education
• /
• v.15 no.2
• /
• pp.192-212
• /
• 2022

The purpose of this study is to analyze scientific attitude and its components in the general remarks and in the particulars of one government-designated and seven authorized elementary school science teacher's guides for the 3rd~4th grades which were developed according to the 2015 national science curriculum, and to derive implications for future development of teacher's guide. The results of the study are as follows: First, in their general remarks, five of eight teacher's guides (62.5%) give a very brief explanation on the components of scientific attitude, and the remaining three teacher's guides give a relatively detailed explanation on the components but they lack practical information on teaching and assessing of the components; Second, in the case of unit objective in the four units of the area of 'Earth and Universe', five of eight teacher's guides (62.5%) contain 3~4 components among 'curiosity', 'cooperation', 'objectivity', 'critical mindedness', or 'respect for evidence', and one of the remaining three teacher's guides contains only the component of 'curiosity', another guide doesn't have any component, and the other guide doesn't have unit objective itself; Third, in the case of unit assessment, only one of eight teacher's guide (12.5%) has independent unit assessment, includes several components of scientific attitude in the unit assessment, and is broadly consistent between the components of scientific attitude in unit objective and in unit assessment; Fourth, in case of lesson objective, three teacher's guide (37.5%) contain 3~4 components among 'curiosity', 'cooperation', 'objectivity' and 'critical mindedness', and the remaining five teacher's guide (62.5%) include only 'curiosity'; Fifth, in the case of lesson assessment, among eight teacher's guides, five (62.5%) evaluate 3~4 components of scientific attitudes, two (25.0%) evaluate only 'curiosity' and 'cooperation', and one (12.5%) does not evaluate anything.

• Journal of Korea Foundry Society
• /
• v.42 no.6
• /
• pp.337-346
• /
• 2022

In order to optimize the solution treatment conditions of Al-7Si-(0.3~0.5)Mg-(0~0.5)Cu alloys, a series of heat treatment experiments were conducted under various solution treatment times up to 7 hours at 545℃, followed by a microstructural analysis using optical microscopy, FE-SEM, and Brinell hardness measurements. Rapid coarsening of eutectic Si particles was observed in the alloys during the first 3 hours of solution treatment but the size of those Si particles did not change at longer solution treatment conditions. Meanwhile, the degree of spheroidisation of eutectic Si particles increased until the solution treatment time was increased up to 7 hours. Q-Al5Cu2Mg8Si6 andθ-Al2Cu were observed in as-cast Cu-containing Al alloys but the intermetallic compounds were dissolved completely after 3 hours of solution treatment at 545℃. Depending on the initial Mg composition of the Al alloys, π-Al8FeMg3Si either disappeared in the alloy with 0.3wt% of Mg content after 5 hours of solution treatment or remained in the alloy with 0.5wt% of Mg content after 7 hours of solution treatment time. Mg and Cu content in the primary-α phase of the Al alloys increased until the solution treatment time reached 5 hours, which was in accordance with the dissolution behavior of Mg or Cu-containing intermetallic compounds with respect to the solution treatment time. From the results of microstructural changes in the Al-7Si-Mg-Cu alloys during solution treatment, it was concluded that at least 5 hours of solution treatment at 545℃ is required to maximize the age hardening effect of the present Al alloys. The same optimal solution treatment conditions could also be derived from Brinell hardness values of the present Al-7Si-Mg-Cu alloys measured at different solution treatment conditions.