• Economic and Environmental Geology
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• v.36 no.1
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• pp.17-25
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• 2003

Researches were carried out to investigate the characteristics and concentration of heavy metal elements of stream water through Dongmyoung abandoned metal mine and soil adjacent to the mine. The pH range of water was 5.9∼7.1 that implies the water environment was acidic to neutral. The contents and distribution aspects of heavy metals in water samples varied with geochemical characteristics of element, but the concentration of heavy metals has the tendency of increase closer to the mine in general. The results of soil analysis show that total heavy metal concentration of agricultural soil near mine was far lower than those of ore tailing and dumping site. Therefore, the effects of the abandoned mine on stream water and agricultural products were supposed to be insignificant, particularly because the portion of absorbed carbonates and reducible fractions among total heavy metal concentration was relatively lower than the other. Since, however total heavy metal concentrations of mining site were relatively higher than those of adjacent region, there is a possibility of heavy metal difussion when the chemical environment of the site changes due to migration of surface and underground water. It is suggested that the preventive measures for water and soil pollution by the heavy metals would be considered around the region.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.127-134
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• 1994

As a series of studies to investigate the effect of immunosuppression on Ascaris suum infection in undefinitive hosts, a delicate relationship between host and parasite, in the present studies golden hamsters were alloted to experiment 1(normal undefinitive host group) and experiment 2(immunosuppressive group treated with prednisolone acetate) and inoculated with a single dose of 1,500 embryonated Ascaris suum eggs. The recovery rates, sizes and features of the larvae and immunological responses in the hamsters were chronologically monitored according to somatic migration. In both experiments, the larvae failed to develop into the adults, but the more and larger larvae were observed for a longer period from experiment 2 in comparison with experiment 1. The numbers of the mast cells in the small intestinal mucosa and mesenteric lymph nodes, of the goblet cells in the small intestinal mucosa and of T-cells in the mesenteric lymph nodes, spleens and cardiac blood from experiment 2 were fewer than those from the experiment 1. In general, increasing of these cells followed by expulsion of the worms in the both groups. Profound leukopenia due to lymphopenia was found through trial period in experiment 2. Considering the experimental results, development or expulsion mechanism of somatic migrant larvae may be related to lymphopenia and temporary increasing tendency of the mast cells, the goblet cells and T-cells. In addition, patent infection of A suum in the hamsters was not obviously observed in spite of immunosuppression by prednisolone acetate.

• Korean Journal of Materials Research
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• v.19 no.3
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• pp.137-141
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• 2009

Density functional theory was utilized to investigate the growth of an indium nanowire on a Si (001) buckled surface. A site between the edge of two Si dimers is most favorable when the first In atom is adsorbed on the surface at an adsorption energy level of 2.26 eV. The energy barriers for migration from other sites to the most favorable site are low. When the second In atom is adsorbed next to the first In atom to form an In dimer perpendicular to the Si dimer row, the adsorption energy is the highest among all adsorption sites. The third In atom prefers either of the sites next to the In dimer along the In dimer direction. The fourth In atom exhibited the same tendency showed by the second atom. The second and fourth In adsorption energy levels are higher than the first and third levels as the In atoms consume the third valence electron by forming In dimers. Therefore, the In nanowire grows perpendicular to the Si dimer row on the Si (001) surface, as it satisfies the bonding of the three valence electrons of the In atoms.

• Korea journal of population studies
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• v.30 no.2
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• pp.147-168
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• 2007

The objective of this study is to examine the studies of foreign workers in Korea at a level of meta-analysis focusing on their subjects and methodology. Over the last 15 years, studies of foreign workers have diversified subjects and refined methodology reflecting major characteristics of migration patterns including a rapid increase in number, large populations of illegal sojourners, a majority low-skilled young male workers from less developed countries, and an active role of migrant-support NGOs. Nevertheless, the studies have shown problems such as a higher ratio of macroscopic discussions, overemphasis on social problematic issues and a tendency towards descriptive analysis. Methodologically, they have also revealed an inactive use of empirical and quantitative data, lack of representativeness of sample and disregard of an importance of language in the study of foreigners. Based on the analysis, this study proposes strategies to enhance researches of foreign workers in Korea.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.3
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• pp.74-83
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• 1998

The phenomenon of decrease in sizing efficiency when the stock temperature is increased is well recognized as summer sizing, and this is believed to be caused by uneven distribution of sizing agents on paper surface most often incurred by coagulation of sizing agents. When unevenly sized paper is used as coating base stock, nonuniform consolidation of the coating layer may result, which, in turn, causes uneven distribution of binder on coating surface. This causes nonuniform ink absorption to produce print mottle. In this study the effects of simple or polymeric electrolytes, storage temperature and time on the coagulation of cationic dispersed rosin size were investigated using a turbidity measurement method which was verified to correlate well with the particle size of rosin emulsion or its coagulates. Handsheets sized with rosin dispersions coagulated under various conditions were prepared and their sizing degree and coated paper properties including gloss and ink density were examined. The relationship between the sizing nonuniformity of coated papers and its ink absorption property was evaluated. Turbidity of rosin emulsion increased as the storage temperature and time were increased. Addition of simple or polymeric electrolytes caused reduction in $zeta$ -potential of the rosin dispersion and accelerated the coagulation tendency substantially. Reversion of the $zeta$ -potential of rosin dispersion, however, did not occur when coagulation was induced with simple electrolytes. On the other hand, addition of an anionic polyelectrolyte reversed the $zeta$ -potential of the flocculated rosin dispersion. This indicated that electrical double layer compaction and bridging flocculation were coagulation mechanisms for simple and polymeric electrolytes, respectively. Sizing degree decreased as coagulation of rosin was increased. Paper gloss, ink gloss and ink density were increased when sizing degree of base stock was increased most probably due to prevention of base paper swelling and increased binder migration to coating surface. This suggested that uneven printing ink density occurred when uneven sizing development was induced by coagulation of rosin particles.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.20 no.1
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• pp.221-234
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• 2009

The purpose of this study is to analyze how the satisfaction of Korea life and attitude on sending information is influenced by the information cognition rate of Korea before influx to Korea. The method used for this study was to survey migrant workers in Busan and Kyeongnam area. The results show a tendency towards a higher information cognition when the information was acquired through manpower supply agencies and media information. In addition, among the variables of information cognition, when 'socio-economical' factor was high, the satisfaction rate of Korea life tended to be higher. Also, when the 'workplace environment satisfaction' factor was high, attitude on sending information tended to be positive. Based on those results, this study presented measures for establishing information policies, such as provision of high quality information, diversification of information route which are necessary for migrant workers.

• Journal of Information Technology Services
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• v.23 no.3
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• pp.17-37
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• 2024

This study explores the tendency of corporations and organizations to continue with their current processes despite having incentives for better Information Technology (IT) innovation or transition. In this context, the study argues that organizations may struggle with 'outsourcing inertia,' a well-known concept referring to an organization's deficient adaptability to environmental changes, particularly defined here as the organization's slow adaptation to changes in outsourcing levels. To verify this, the study analyzes how key variables identified from existing IT Outsourcing (ITO) decision-making research and recent studies on cloud computing transitions actually affect a firm's transition intentions. In the process, this study investigates the moderating effect of a firm's outsourcing inertia, utilizing the Technology-Organization-Environment (TOE) framework and the Push-Pull-Mooring (PPM) model based on migration theory to propose a research model. The study aims to contribute to finding strategic approaches necessary for facilitating IT innovation and transition by understanding the impact of outsourcing inertia on the decision-making process related to IT outsourcing. It is important to note that the majority of domestic conglomerates own IT subsidiaries, which significantly influence the process of transitioning to cloud computing. Nevertheless, research on the impact of IT subsidiaries on cloud computing transition is relatively scarce. Based on this background, this study proposes that IT subsidiaries within domestic conglomerates can act as a significant mooring factor of organizational inertia in the decision-making process for adopting cloud computing. Through this, the study seeks to provide strategic insights for overcoming organizational inertia faced by IT subsidiaries during the cloud computing transition process.

• Journal of Wetlands Research
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• v.23 no.4
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• pp.317-326
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• 2021

The present study was carried out with a view to understand the distribution and ecology of Clihton retropictus (Martens, 1879), a class II endangered wildlife designated and protected by the Ministry of Environment, Republic of Korea, and to suggest the effective conservation and management measures for this species and its habit. First, the distribution of Clihton retropictus was investigated nationwide, and environmental factors such as salinity and substratum were analyzed in consideration of the ecological characteristics of this species. In addition, the individual size, density, and movement of Clihton retropictus per each district surveyed were analyzed. Due to its nature of inhabiting in the brackish water zone, the analysis showed that the salinity of this species was 0.7 ~ 16.6‰ at low tide and 1.0 ~ 17.3% at high tide. It was learned from the analysis of substratum that its composition in each river under investigation was slightly different, but most of substratum had a higher composition ratio than gravel (pebble, 16 ~ 64 mm). On the other hand, the size of each individual was checked by measuring the length of its diameter, and there was almost no change in the individual when the inhabited range of Clihton retropictus was short. However, there was tendency that the longer the habitat range, the bigger the individual size. From surveying the population density by season, it was made clear that, during the summer (July to August) and fall (September to October), the density was relatively higher while the number of individuals decreased significantly during winter (November to December) when the water temperature was lowered. In an effort to effectively establish conservation and management measures, the moving distance was measured, and it became known that, during the surveys in summer and fall when the individuals were active, the individuals moved in more distances than during the winter survey. The results of this study are expected to be utilized as basic data for establishing effective management plans such as creation of habitats for Clihton retropictus, its migration projects and selection of migration destinations which get unavoidable due to development projects.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.13 no.1
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• pp.3-14
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• 2002

Childhood psychic trauma appears to be a crucial factor in the development of serious disorders both in childhood and in adulthood. Traumatized children show strong tendency to revisualize or re-feel a traumatic events. Play and behavioral reenactments are frequent manifestations of both the single blow and the long-standing traumas in childhood. Those children who suffer the results of single, intense terror appear to exhibit detailed memory, retrospective reworkings and misperceptions. In long-standing or repetitive trauma, children would show psychic numbing, self-hypnosis, dissociation and rage. Child's brain is undergoing critical and sensitive periods of differentiation. During this time, developing central nervous system is exquisitely sensitive to stress. Stressor-activated neurotransmitters and hormones can play major roles in neurogenesis, migration, synaptogenesis, and neurochemical differentiation. Internal opiate system operates in some trauma and causes the victim to fail to respond, to avoid, to shut off feelings. Evidence is also accumulating in traumatology that dysfuntion of locus coeruleus and ventral tegmental neucleus system leads to catecholamine receptors hypersensitivity. This change result in hypervigilance, increased startle, affective lability, and increased autonomic nervous system hyperreactivity. Another site of action of trauma on the brain is hypothalamic-pituitary-adrenal axis. Individuals with PTSD do not have enough cortisol to halt the alarm reaction. When children are exposed to long-standing extreme events, massive attempts to protect the psyche and to preserve the self are put into gear. These developmental traumas mobilize various kinds of defense mechanisms. Massive denial, dissociation, self anesthesia, identification with aggressor and aggression turned against the self often lead to profound character changes in the youngsters.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.3
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• pp.189-195
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• 2001

The characteristics of echolocation signals of the Common Dolphin, Delphinus Delphis was observed by the hydrophone in order to detect exactly distribution and migration on whales and dolphins in Korean Coastal waters. It's observation was carried out at the position of 13 mm off Gam-Po of Korean east-southern sea at 3rd-5th. April and 13th-15th. October, 1999. The results obtained are summarized as follows: (1) The frequency range of ship's noise and ambient noise in the observed station was 0.5-0.3 kHz, that ones could be influenced to the behavior of common dolphins which carry out echolocation using low-frequency. (2) The common dolphin was radiated single click of 8.6 ms and double click of 4.8 ms pulse width during these observation (3) The high click frequencies of common dolphin were 5.10 kHz, 7.22 kHz, 10.60 kHz with the click pulse width of 4.0 ms, 2.6 ms, 1.0 ms, respectively. In case of low-frequency 1-2 kHz, that is, 1.12 kHz, 1.38 kHz, 1.82 kHz, pulse width were 22.4 ms, 2.05 ms, 11.9 ms, respectively and they showed a tendency using triple click signal. (4) The pulse width, pulse recurrence interval and frequency range of the observed echolocation signals were 2.4-8.4 ms, 9.0-40.0 ms, 0.60-10.63 kHz respectively, and frequency spectrum level was 100-125 dB for single, double, triple click signals.