• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.318-333
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• 2020

The Nakdong-Jeongmaek extends north and south from Taebaek-si of Gangwon-do to Busan metropolitan city and includes a wide range of forest zone from temperate to the warm-temperature forest. The purpose of this study was to analyze the vegetation structural characteristics of the Quercus mongolica-dominant community, which was distributed in the largest area in Baekdudaegan and Jeongmaek, by region and communities in the Nakdong-Jeongmaek. For the study, a representative 6 sites were selected: Baekbyeongsan, Chilbosan, Baegamsan, Unjusan, Goheonsan, and Gudeoksan. The survey of the 6 sites showed that the canopy had over 85% the importance percentage of Quercus mongolica. In the understory, Rhododendron schlippenbachii, Fraxinus sieboldiana, etc. were located and Fraxinus sieboldiana, Lespedeza maximowiczii, Tripterygium regelii and so on were found in the shrub. The importance percentage of 4 communities of Quercus mongolica, which were separated by TWINSPAN, in the canopy was more than 80%, and the dominant species in the understory and shrub were the same. Currently, Quercus mongolica has been identified as the understory following the canopy, and the Quercus mongolica-dominant community is expected to continue unless there are external factors. In the temperate forest regions in Korea, Quercus spp.and Carpinus laxiflora form the major forest physiognomy in the natural forest state. Based on these characteristics, the Quercus mongolica-dominant community on the ridge of the Nakdong-Jeongmaek is considered to have characteristics of temperate forests in Korea. The Quercus mongolica community is a representative cool-temperate deciduous forest and known as a climatic climax in the upper section of the mountains in the Korean Peninsula. Trees of the same species should be distributed at each layer to maintain the dominant species' status in the canopy's climax forest. Therefore, the Quercus mongolica community is considered the climax forest in the ridge of the Nakdong-Jeongmaek.

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.285-292
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• 2011

In plants, heteroblasty reflects the morphological adaptation during leaf development according to the external environmental condition and affects the final shape and size of organ. Among parameters displaying heteroblasty, leaf index is an important and typical one to represent the shape and size of simple leaves. Leaf index factor is eventually determined by cell proliferation and cell expansion in leaf blades. Although several regulators and their mechanisms controlling the cell division and cell expansion in leaf development have been studied, it does not fully provide a blueprint of organ formation and morphogenesis during environmental changes. To investigate genes and their mechanisms controlling leaf index during leaf development, we carried out molecular-genetic and physiological experiments using an Arabidopsis mutant. In this study, we identified macrophylla (mac) which had enlarged leaves. In detail, the mac mutant showed alteration in leaf index and cell expansion in direction of width and length, resulting in not only modification of leaf shape but also disruption of heteroblasty. Molecular-genetic studies indicated that mac mutant had point mutation in ROTUDIFOLIA3 (ROT3) gene involved in brassinosteroid biosynthesis and was an allele of rot3-1 mutant. We named it mac/rot3-5 mutant. The expression of ROT3 gene was controlled by negative feedback inhibition by the treatment of brassinosteroid hormone, suggesting that ROT3 gene was involved in brassinosteroid biosynthesis. In dark condition, in addition, the expression of ROT3 gene was up-regulated and mac/rot3-5 mutant showed lower response, compare to wild type in petiole elongation. This study suggests that ROT3 gene has an important role in control of leaf index during leaf expansion process for proper environmental adaptation, such as shade avoidance syndrome, via the control of brassinosteroid biosynthesis.

• The Korean Journal of Malacology
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• v.29 no.1
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• pp.51-63
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• 2013

To assess the effect of environmental factors on the sustainability of cultured production shellfish, we investigated the habitat characteristics of tidal flat (Namhae-po in Taean). We measured the physiochemical parameters (temperature, salanity, pH, dissolved oxygen and nutrients) and the geochemical characteristics (chemical oxygen demand, ignition loss, C/N ratio and C/S ratio). Surface sediments were collected from several site of tidal flat to examine the geochemical characteristics of both the benthic environment and heavy metal pollution. The grain size for research area of tidal flat were similar at the ratio of silt and clay in comparison with the other site of it. The C/N ratio was more than 5.0, reflecting the range arising from the mix of marine organism and organic matter. The C/S ratio (about 2.8) showed that survey area had anoxic or sub-anoxic bottom conditions. The enrichment factor (Ef) and index of accumulation rate (Igeo) of the metals showed that those research areas can be classified as heavily polluted, heavily to moderately polluted, or more or less unpolluted, respectively. Adult surf clam (Mactra veneriformis) density was highest at St. 2 (middle part of the Namhae-po), on the other hand, surf clam spat density was highest at St. 3 (lower part of the Namhae-po). Heavy rain, terrigenous suspended clay with fresh water from neighboring agricultural land, and severe high air temperature during summer could be thought as detrimental causes of spat and adult mortality in Namhae-po tidal flat. We suggested that the growth of shellfish in the tidal flat was effected by the various environmental conditions, so an improvement in the cultured method was needed.

• Journal of Digital Convergence
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• v.18 no.10
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• pp.81-93
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• 2020

This study is based on workplace learning, which has revealed its significant influence in the previous enterprise case studies. Why do small business owners have the opportunity to participate in workplace learning based on authenticity? It was intended to clarify whether it was necessary and to increase the growth and development potential of small business owners based on its contents. Moreover, this study is focused on identifying the influence of workplace learning on management performance through this series of processes. In order to investigate the influence of small enterprise workplace learning on management performance, research hypotheses were set based on a review of previous studies, and empirical analysis was carried out. A total of 203 questionnaires were empirically analyzed using SPSS 18.0 program. As a result, first, workplace learning had partially significant positive influence on job satisfaction. Second, workplace learning had significant positive influence on management performance. Third, job satisfaction had significant positive influence on management performance. Fourth, job satisfaction had partial mediating effect in the relationship between workplace learning and management performance. The analysis result showed that among sub-factors of workplace learning, only formal learning did not affect job satisfaction and that job satisfaction did not have mediating effect in the relationship between formal learning and management performance. According to analysis, this was because in poor small enterprise environments, opportunities to participate in formal learning like external training or in-house training were not kept. In other words, poor small enterprise environments were plainly revealed from the managerial, economic and social standpoint. Therefore, there is a need to establish the foundation of growth for them to solve problems and develop win-win development capabilities and an institutional system that can make a contribution to policy and education, and management, by helping small enterprises keep opportunities to participate in workplace learning. In spite of these significant study results, there can be a limitation. For improving this limitation, further research will need to target diverse fields focusing on samples, which can explain relations of many different variables. Also, working-level relation research connected to studies that can highly enhance management performance will be required.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.649-657
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• 2011

This study had targeted the Manjong Junction~Hongchun interchange section of Jungang highway in order to analyze the efficiency and improvement of the highway wild-life fences. Being analyzed wild-life fence as an effective facility for the prevention of road-kill, it had founded that the wild animals did not jump over even the two layer guardrail, concrete barrier and noise barrier, fence for rock fall. For the section with high road-kill decrease effect after installing the wild-life fence, the effect was higher at wild-life fence with the height of 1.0m where the door had not been installed and the well connected points of road facility than the area with fence height of 1.5m. The road-kill decrease effect was also high at the well managed areas even if the door has not been installed. Also, road-kill had occurred by concentrating around the end of wild-life fence after installing the fence, Moreover road-kill had also occurred around the cutting section. The door of wild-life fence had higher amount of road-kill occurrence as the installation interval was closer. it was analyzed that the door management has a lot of effect on road-kill decrease. The fence for rock fall, two layer guardrail and concrete barrier having the effect of wild-life fence installed on the road would have to be installed by connecting with wild-life fences through proper facility improvement. Although the door should not be installed if possible, it should be installed as automatic door or gravity door to prevent the door from leaving the door open. An escape route has to be formed for the prompt escape away from the road for the animals entered through the ending section of the fence. The eco-corridor has to be made by restoring the soil layer of dual purpose eco-corridor forming a planting area. Also, the dead body after the accident has to be disposed to the outer section of the road immediately in order to prevent the secondary road-kill by the predator from the road-kill. The fence has to be installed as 500m or longer in both ways, in other words 1,000m or longer, from the targeted spot of minimum accident prevention while connecting up to the bridge or box culvert, etc that are next road facilities if possible to guide wild animals safely to the eco-corridor.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.2
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• pp.74-81
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• 2017

An off-site consequence analysis is used to calculate the risks when hazardous chemicals that is being used on-site has been exposed off-site; the biggest factor that impacts the risk is the risks of accident scenarios. This study seeks to calculate risks according to accident scenarios by applying OGP/LOPA risk calculating methods for similar facilities, calculate risk reduction ratio by inspecting applicable IPL for incidents, and propose an appropriate risk standard for different risk calculating methods. Considering all applicable IPL when estimating the safety improvement of accident scenarios, the risk of OGP is 8.05E-04 and the risk of LOPA is 1.00E-04, According to the case of IPL, the risk is 1.34E-02. The optimal risk level for accident scenarios using LOPA was $10^{-2}$, but the appropriate risk criteria for accident scenarios in foreign similar studies were $10^{-3}{\sim}10^{-4}$, the risk of a scenario can be determined at an unacceptable level. When OGP is applied, it is analyzed as acceptable level, but in case of applying LOPA, all applicable IPL should be applied in order to satisfy the acceptable risk level. Compared to OGP, the risk is high when LOPA is applied. Therefore, the acceptable risk level should be set differently for each risk method.

• The Korean Journal of Petroleum Geology
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• v.3 no.1 s.4
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• pp.1-15
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• 1995

Seismic reflection profiles and exploratory drilling well samples from the southern marginal-continental shelf basin of Korea delineate that the Tertiary sedimentary sequences can be grouped into five sequences (Sequence A, Sequence B, Sequence C, Sequence D and Sequence E, in descending order). Paleontologic data, K-Ar age datings, correlation with tuff layers and sequence stratigraphic analysis reveal that the sequences A, B, C, D and E can be considered as the deposits of Holocene $\~$ Pleistocene, Pliocene, Late Miocene, Early $\~$ Middle Miocene and Oligocene, respectively. The sequence stratigraphic and structural analyses suggest that the southern part of the Cheju Basin had experienced severe folding and faulting. NE-SW trending strike-slip movement is responsible for the deformation. The sinistral movement of strike-slip fault ceased before the deposition of Sequence B. Age dating and rare-earth elements analysis of volvanic rocks reveal+ that the Sequence D was deposited during the Early $\~$ Middle Miocene and the Sequence I was deposited earlier than the deposition of the Green Tuff Formation. Sedimentary petrological studies indicate that sediments of the Sequence I came from the continental block provenance. After the deposition of the Sequence E, uplift of the source area resulted in increase of sediment supply, subsidence and volcanic activities. The Sequence D show these factors and the sediments of the Sequence D are considered to be transported from the recycled orogenic belt.

• 대한공업교육학회지
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• v.45 no.2
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• pp.21-45
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• 2020

The purpose of this study was to verify how the vocational education for training industrial workforce as a national human resource development (NHRD) system has undergone a transition process in relation to the national economic, industrial, and socio-cultural contexts. First, how vocational education as an industrial workforce training system has changed in accordance with Korea's economic environment, industrial development, and social changes; second, what are the main factors that influenced the role and importance of vocational education; and third, vocational education as a system for training industrial workforce and training workforce in science and engineering were analyzed differently from the perspective of the NHRD model. To this end, domestic and international academic journal papers, research reports, and thesis were investigated and classified by period, and major changes in vocational education were analyzed in relation to economic, industrial, and social issues and policies by period. As a result of the research, first, as the industry advanced, the level of vocational education increased and the scope expanded. Second, vocational education tended to shrink gradually after the manufacturing industry base, and especially secondary vocational education tended to decline after the national industry focused on light industry. Third, since the 1970s, the diversification of the NHRD and jobs has resulted in wage gaps depending on the level of education, which has increased the preference for university education and avoided secondary vocational education. In addition, a NHRD model focusing on training science and engineering workforce was proposed to compare the existing NHRD model focusing on overall vocational education, and it was revealed that the NHRD needs to be subdivided into various fields or levels to derive a model and examine changes. From the results of the study, vocational education in Korea, especially in secondary vocational education, has declined due to large impacts on socio-cultural perception due to economic growth, enthusiasm for education, and external shocks such as the financial crisis, and the long-term effort to change this perception is suggested to overcome the crisis of vocational education.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1308-1314
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• 1999

The effects of modified atmosphere(MA) packaging and coating on the quality of mushroom (Agaricus bisporus) were investigated. Whole mushrooms(100 g) were packed with polyvinyl chloride(PVC) film wrap, PD941 and PD961 film bags and were stored in a chamber at $12^{\circ}C$ and 80% RH for 6 days. Gas composition of packages, respiration rate, weight loss, color and maturity index of MA packaged mushrooms were examined. The wrap packaged mushrooms showed different level of internal $CO_2$ concentrations among water washed, chitosan coated and $CaCl_2$ coated subgroups significantly at 5% level. The maximum $CO_2$ concentration of PD941 and PD961 packages for all coated showed $4.1{\sim}4.7%$ and $10.4{\sim}11.7%$, respectively, for the first day. PD961 package showed the lowest $O_2$ concentration compared to other groups. There were no significant respiration rate differences between wrap packed and PD941 packaged. Respiration rate of water washed. chitosan coated and $CaCl_2$ coated in PD961 packaged was 192 mg, 226 mg and 245 mg, respectively. Maturity index of PD961 packaged were not significantly different among the water washed, chitosan and $CaCl_2$ coated packages. Chitosan coating showed a negative effect on color change of mushrooms. The weight loss of 961 packaged was lower $(7.0{\sim}8.0%)$ that those of wrap packaged and PD941 packaged.

• Korean Security Journal
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• no.18
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• pp.119-141
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• 2009

Administrative execution by proxy is one of forced executions of administration and is also called as "enforced execution by proxy" in which administration institutions or the third party executes by proxy on behalf of parties who did not execute obligations under administration law and files claims to compensate expenses required in the proxy execution. Despite the actual site of administrative execution by law, social problems are generated because various violence and behaviors of infringement of human rights between executer and obligator are rampant and thus causing human damages since forced execution by physical force is carried out and cases of police indictments and petition to human rights committee are gradually increasing. Majority of people mobilized in this actual site of violence are supplied by private security companies which provide service contract and mobilization of people without qualification of guards or security service and irrational execution by proxy and violent actions by so-called service hooligans connected to violence organizations are now becoming social issues. In these actual sites of violence, structurally very complicated problems such as economic rights, right of residence, struggle for living, and intervention by outsiders are contained. This thesis has analyzed causes of outbreaks of violence and discussed about improvement countermeasure by paying attention to mobilization of people by private security companies. As the result, through revision and improvement of laws and systems, execution institution and policemen must be present at actual sites of execution by proxy to control physical execution of private security companies to be carried out legally and when violent collisions are occurring, it shall be stipulated that police should immediately intervene. Practices of execution by proxy of execution administration institutions shall be avoided and causes of occurrences of violence shall be eliminated by discrete decisions of execution by proxy, elimination of service contract conditions focused on accomplishments, and stipulation of responsibility of execution institutions when problems occur. Practices of solving petitions through collective actions of obligators shall be eliminated and strict enforcement of laws such as disturbance of official execution or compensation claims for expenses of execution by proxy must be carried out and intervention by the third parties must be intercepted. Mobilization of manpower by security companies shall be limited to people with prior registration who have acquired and finished qualification and education by security business law and before putting them on actual sites, it shall be obliged that execution plan with clear written records of working location, mission, and work rules must be submitted in advance to police station in charge and also they must be controlled to follow laws and statutes such as uniform and equipments. In addition, personal criminal responsibility for violent actions must be clearly stipulated and advanced securing soundness of security companies such as limits of service contracts with records of accidents is required. Order placement behaviors of special organizations under the pretext of rehabilitation business must be eradicated and companies with capability and strong intention of observation of laws must be able to receive orders by intercepting chains of contracts and sub-contracts. Issues of improvement countermeasure of social problem, living, and compensation including rights of residence and environment are excluded from the discussion.