• The Korean Journal of Ecology
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• v.25 no.1
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• pp.1-7
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• 2002

The ecological background of a restoration project is complex and difficult to betermine without experimentation. A useful context for experiments is the well-studied process of natural succession, because the factors that drive or inhibit succession are also at work during reclamation (a form of primary succession) and restoration (which often resembles secondary succession). Using experimental studies on urban wasteland reclamation, we have tested for factors that stimulate or inhibit succession during early phases of woodland development in the Northeastern United states. The emphasis has been on mutualisms (seed dispersal, pollination, and mycorrhizae) and microsite limitations in the recruitment, growth, and reproduction of woody plants. Using plantings of seeds, seedlings, and clusters of reproductively mature plants on abandoned landfills, we have observed that (1) soil microsite deficiencies lead to very poor germination (<0.1$\%$) and seedling survival (<0.01$\%$) of most native species; (2) seed dispersal by birds is a significant and reliable source of woody plant recruitment; however (3) proximity effects are strong, with most (up to 95$\%$) of seed rain falling in the vicinity of planted clusters that are closest to putative seed sources; and (4) remnant natural woodlands are critical components of the recruitment process. To emphasize the last point, in one case, we found that the destruction of approximately 50$\%$ of nearby natural woodland vegetation led to a commensurate decline in seed rain. In another case, we found that the species richness of recruits was strictly limited by the species composition of nearby source plant communities, with no evidence of community enrichment by long distance dispersal over 5 years. We conclude from these results that the size and proximity of remnant natural populations are critical considerations when planning reclamation and restoration programs that rely on natural successional processes.

• Journal of the Ergonomics Society of Korea
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• v.35 no.6
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• pp.611-619
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• 2016

Objective:This study aims to analyze the relationships between personality factors measured by Minnesota Multiphasic Personality Inventory (MMPI) scales and the indices of safety and health in the shipbuilding industry. Background: Many researches reported that there were significant relationships between some MMPI subscales and traffic and industrial accidents. Method: This study analyzes 230 male workers in shipyard for their MMPI scores gathered during recruitment process and their safety and health indices from the performance record during their working period. ${\chi}^2-test$ and one-way ANOVA are used for finding the statistical significance for personality factors. The conventional grouping rule for MMPI scales and other grouping criteria considering the attitude of positive answer for the MMPI test during recruitment process are used for analysis. Results: The Hypomania (Ma) and Psychopathic Deviate (Pd) scales of the MMPI are the main factors related to the safety and health related indices for most grouping rules. Depression (D), Psychasthenia (Pt), Hypochondriasis (Hs), Schizophrenia (Sc), and Masculinity and Femininity (Mf) scales are also related to the safety and health indices. Conclusion and Application: The results can be used for understanding the psychological factors in human behaviors and safety and can help professional personnel take the necessary steps in improving safety on the job and also in providing the effective teaching of safe work methods.

• Ocean and Polar Research
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• v.39 no.4
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• pp.257-267
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• 2017

Although Pacific mackerel (Scomber japonicus) is an important commercial species in Korea, its recruitment mechanism remains largely unknown. Diel vertical positioning of larvae in the water column, which is affected by their specific gravity and the surrounding water density, may help to provide an understanding on recruitment success through predator avoidance and prey availability. The specific gravity measurement on Pacific mackerel eggs and larvae would seem to be essential information necessary to learn about the transport process from spawning to nursery grounds, and consequently the recruitment success. Eggs were artificially fertilized, and larvae were fed with rotifer when their mouths opened 3-4 days after hatching. We conducted the experiment using a density gradient water column to measure the ontogenetic changes in specific gravity from fertilization to 10 days after hatching. Egg specific gravity was stable during most of the embryonic period, but a sudden increase to $1.0249g\;cm^{-3}$ happened just before hatching. However, the specific gravity of newly hatched larvae was much lighter ($1.0195g\;cm^{-3}$), and specific gravity tended to increase continuously after hatching. Comparison of specific gravity with seawater density reveals that eggs and newly hatched larvae can float in the surface layer of the ocean. For the later period of the experiment, the specific gravity showed a cyclic diel pattern: the highest in the evening while the lowest at dawn. The fullness of larval stomach may be responsible for the observed differences in specific gravity, because stomach fullness was lower (40-60%) at midnight, and higher (80-85%) in evening. The diel pattern of specific gravity might provide clues regarding how larvae match the diel vertical migration of prey organisms.

• Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.281-286
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• 2002

Artificial reefs were set on a sandy bottom substratum at 8m, 10m and 13m depths along the coast in Muronohana, Ikata, Japan. Succession of seaweed communities was observed monthly or bimonthly from February 1999 to August 2000 on artificial reefs. Within one month, the diatom colonized on the reefs with coverage of $100\%$. After three months, Enteromorpha intestinalis and Colpomenia sinuosa dominated on the reef in the spring. Seaweed flora decreased during the summer and the dominant species were several species of Melobesioidea. In the winter, the seaweeds grew up again and the dominant species on the each reef were Sargassum spp., Ecklonia kurome and Padina arborescens after one year. The dominant species in the algal succession process changed from diatoms to the perennial seaweeds such as Sargassum spp., E. kurome and P. arborescens. Thus, the pattern of succession of the dominant species and the degree of domination were changed by the season, water depth and the recruitment of spores and eggs from the mature alga around the reefs.

• Journal of agricultural medicine and community health
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• v.31 no.2
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• pp.119-144
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• 2006

The Korea rural health study, a large prospective cohort study, the objectives of this study are exploration for potential causes of agricultural injuries and diseases among farmers. Current medical research suggests that they may have higher rates of some traumatic injuries, pesticide poisoning, infectious diseases, musculoskeletal diseases, asthma and other respiratory diseases. This study is designed to identify occupational, lifestyle, and environmental factors of workplace that may affect the rate of diseases in farming population. Round 1, initial cohort recruitment, will begin in 2006 and conclude in 2009. Round 2, follow-up will begin in 2010 and conclude in 2014. Approximately 54,000 persons will be selected to study population. Nested case-control studies and case-crossover studies will be conducted for getting to the bottom of agriculture-related diseases. Recruitment and follow-up are conducted in collaboration with multi-centers. As data on the exposures and health outcomes of this study population are collected and analyzed in 2014. This study will be evaluated by public health experts for effort, achievement, adequacy of performance, efficacy, process of study and so on. The author expects that this cohort study may reduce agricultural injuries and diseases and will provide information that agricultural workers can use in making decisions about their health. Also, this study will be significant basis for strengthening the competitiveness of agriculture in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.3
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• pp.292-301
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• 2024

It is challenging to simultaneously estimate parameters in a stock-recruitment relationship, steepness, and natural mortality rate with the other parameters within an age-structured assessment model even in a data-rich situation. Such a problem leads to uncertainty in estimates of management references such as maximum sustainable yield (MSY), which are affected by those components. The objective of this study was to evaluate the effects of those parameters on MSY by analyzing the process of estimating the MSY. For illustration, we used two data sets: The chub mackerel Scomber japonicus in the Korean waters and the yellowtail flounder Limanda ferruginea in the Southern New England-Mid Atlantic. As a result, the natural mortality rate influenced spawning stock biomass per recruit, yield per recruit, and MSY, while steepness affected MSY. A sensitivity analysis enabled us to estimate the natural mortality rate and steepness. The optimal set of steepness and natural mortality was 1.0 and 0.37 per year for the chub mackerel, and 0.35, and 0.8 per year for the yellowtail flounder, respectively.

• Ecology and Resilient Infrastructure
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• v.1 no.2
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• pp.68-81
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• 2014

In this study, the numerical simulation regarding the process and characteristics of topography change due to the vegetation recruitment and growth was carried out by adding the vegetation growth model to two-dimensional flow and sediment transport models. The vegetation introduction and recruitment on the condition for developing an alternate bar reduced the bar migration. The vegetated area and channel width changes were more significantly influenced by changes in upstream discharge rather than the duration of low flow. When the upstream discharge decreased, the vegetation area increased and the channel width decreased. The vegetation introduction and recruitment on the condition for developing a braided channel significantly influenced the characteristics of topography changes. In the braided channel, vegetation reduced the braided index, and when the upstream discharge decreased significantly, the channel topography was changed from the braided channel to the single channel. The vegetation area decreased as the upstream discharge increased. The channel width decreased significantly after the vegetation was introduced and it also decreased as the upstream discharge decreased. It was confirmed through the numerical simulation that a decrease in flood discharge accelerated the vegetation introduction and recruitment in the channel and this allowed to confirm its influence on the characteristics of topography changes qualitatively.

• Youth Facilities and Environment
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• v.9 no.4
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• pp.49-55
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• 2011

The purpose of this study is to investigate and analysis importance for evaluation indicators in youth centers. The sample of it is 138 youth centers. Method of this analysis of importance for its indicators is AHP(Analytic Hierarchy Process). Evaluation domains in youth center are process evaluation, product evaluation, input evaluation and specialized program in order of importance. Also, it is important to evaluate in needs assessment, recruitment of youth instructor, participation of youth in decision making, connective project with schools, sanitation level of youth center, satisfaction research, efforts of improvement of youth center staff in evaluation indicators. The result of this study is that importance for evaluation indicators suggests developmental directivity in youth center management.

• Korean Journal of Culture and Social Issue
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• v.30 no.2
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• pp.101-120
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• 2024

Due to the expanding roles of corporations, the significance of Corporate Social Responsibility (CSR) has escalated, fostering continued efforts for organizations to integrate CSR into the context of recruitment. Additionally, demand for CSR authenticity is increasing. Damaged CSR authenticity can give rise to negative consequences, but research on the CSR authenticity is lacking, particularly within the realms of job search and recruitment. Consequently, this study aimed to investigate whether organizational attractiveness varies with CSR authenticity (high CSR authenticity, low CSR authenticity, and control conditions) through a scenario design. Additionally, the study examined the mediating effects of value congruence, as well as the moderating effect of moral identity in this relationship. Conducted among 300 undergraduate students, the results indicated that the organizational attractiveness was highest in the high CSR authenticity condition, followed by the control condition, and the lowest in the low CSR authenticity condition. However, the difference between the high CSR authenticity condition and the control condition was not statistically significant. PROCESS macro was employed to analyze the mediating model of value congruence. The results revealed that the mediating effect of value congruence was significant across all conditions. In sequence, examining the moderating effect and the moderated mediating effect of moral identity, it was found that these effects were significant in the high CSR authenticity condition in comparison to the other conditions. The findings of this study suggest the importance of considering CSR authenticity in the context of job search and recruitment and also, provides an insight into the mechanism through which CSR authenticity influences organizational attractiveness.

• Animal cells and systems
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• v.12 no.1
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• pp.1-9
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• 2008

In the developing limb, chondrogenesis is an important prerequisite for the formation of cartilage whose template is required for bone formation. Chondrogenesis is a tightly regulated multi-step process, including mesenchymal cell recruitment/migration, prechondrogenic condensation of the mesenchymal cells, commitment to the chondrogenic lineage, and differentiation into chondrocytes. This process is controlled exquisitely by cellular interactions with the surrounding matrix and regulating factors that initiate or suppress cellular signaling pathways and transcription of specific genes in a temporal-spatial manner. Understanding the cellular and molecular mechanisms of chondrogenesis is important not only in the context of establishing basic principle of developmental biology but also in providing research direction toward preventive and/or regenerative medicine. Here, I will overview the current understanding of cellular and molecular mechanisms contributing to prechondrogenic condensation processes, the crucial steps for chondrogenesis, focusing on cell-cell and cell-matrix interactions.