• Title/Summary/Keyword: 공동현상

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Effects of Optical Characteristics on the Growth of Benthic Microalga, Nitzschia sp. and Its Growth Kinetics of Phosphate for Bioremediation (생물적 환경정화를 위한 부착미세조류 Nitzschia sp.의 생장에 미치는 광학적 특성과 그에 따른 인산염 성장 동력학)

  • Oh, Seok-Jin;Kang, In-Seok;Yoon, Yang-Ho;Yang, Han-Soeb;Park, Jong-Sick
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.4
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    • pp.205-212
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    • 2009
  • To suggest possible to bioremediation by benthic microalgae Nitzschia sp. isolated from the Jinhae Bay, the studies investigated the effects o flight quality and quantity on the growth of Nitzschia sp. and its growth kinetics for phosphate investigated. The Nitzschia sp. was cultured under blue (450 nm), yellow (590 nm) and red wavelength (650 nm) using light emitting diode (LED) and mixed wavelengths using a fluorescent lamp. The maximum specific growth rate showed the Nitzschia sp. under blue wavelength, although photoinhibition was observed above $100\;{\mu}mol\;m^{-2}\;s^{-1}$. Mixed wavelengths were also observed by decreasing the maximum cell density from high irradiances (>$100\;{\mu}mol$ photons $m^{-2}\;s^{-1}$). The compensation photon flux density ($I_0$) calculated from the mixed wavelengths equated to a depth of 4-10 m in Jinhae Bay, and was lower in the summer season than the depth due to suspended matter (ca. 4 m). Thus, the suitable depth for maximum growth of Nitzschia sp. might be extremely limited. In the growth kinetics for phosphate, half-saturation constant ($K_s$) was similar among different wavelengths, although the maximum growth rate was varied among different wavelengths. Because the $K_s$ was high than that of the phytoplankton, Nitzschia sp. might have adapted to the high nutrient concentrations, and have effective nutrient storage in the cell quota. Thus, Nitzschia sp. may be a useful species for bioremediation of the benthic layer in polluted inner bays by means of irradiated specific wavelength as blue.

Institutional approaches in geography -Institutional changes in the Korean financial system- (지리학에서 제도적 접근법에 관한 연구 -한국금융부문의 제도적 변 화를 사례로-)

  • Choi, Jae Heon
    • Journal of the Korean Geographical Society
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    • v.30 no.4
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    • pp.364-388
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    • 1995
  • Even though rarely recognized as a separate approach, the institutional approach in geography is defined as an attempt to seek an explanation of the phenomena of geographical interest through focusing on the effects of institutional structure and actions. It can provide interdisciplinary links with other works and can offer complementary explanations for geographical interests. The concerns for institutions in geography can be found in early studies, the study of the state, the managerial approach, and the regulation approach. The Korean financial systems can provide good examples to apply institutional concepts into creating spatial outcomes, as it has been regarded as a useful tool to promote Korean economic development. Behind the current spatial pattern of financial systems, four different stages of institutional changes are identified in Korea. Each stage has different institutional features reflecting unique spatial implication.

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Multi-purpose Geophysical Measurements System Using PXI (PXI를 이용한 다목적 물리탐사 측정 시스템)

  • Choi Seong-Jun;Kim Jung-Ho;Sung Nak-Hun;Jeong Ji-Min
    • Geophysics and Geophysical Exploration
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    • v.8 no.3
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    • pp.224-231
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    • 2005
  • In geophysical field surveys, commercial equipments often fail to resolve the subsurface target or even sometimes fail to be applied because they do not fit to the various field situations or the physical properties of the medium or target. We developed a geophysical measurement system, which can be easily adapted for the various field situations and targets. The system based on PXI with A/D converter and some stand alone equipment such as Network Analyzer was applied to borehole radar survey, borehole sonic measurement and electromagnetic noise measurement. The system for borehole radar survey consists of PXI, Network Analyzer, dipole antennas, GPIB interface is used for PXI to control Network Analyzer. The system for borehole sonic measurement consists of PXI, 24 Bit A/D converter, high voltage pulse generator, transmitting and receiving piezoelectric sensors. The electromagnetic noise measurement system consists of PXI, 24 Bit A/D converter, 2 horizontal component electric field sensors and 2 horizontal and 1 vertical component magnetic filed sensors. The borehole radar system has been successfully applied to detect the width of the artificial tunnel through which the borehole pass and to image buried steel pipe, while the commercial borehole radar equipment failed. The borehole sonic system was tested to detect the width of artificial tunnel and showed a reasonable result. The characteristic of electromagnetic noise was grasped at an urban area with the data from the electromagnetic noise measurement system. The system is also applied to characterize the signal distortion by induction between the electric cables in resistivity survey. The system can be applied various geophysical problems with a simple modification of the system and sensors.

A Study on the Direction of Mission Education Based on Ecumenical Mission (에큐메니칼 선교에 기초한 선교교육의 방향에 관한 연구)

  • Lee, Eun Joo
    • Journal of Christian Education in Korea
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    • v.66
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    • pp.179-208
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    • 2021
  • Due to COVID-19, the entire world is facing the unprecedented phenomenon. Amid the threat of the virus, the global community is struggling for life. In such circumstances, churches in Korea have been criticised as selfish groups threatening the community by spreading the virus. With such criticism, they are disregarded by Korean society because their immorality and exclusive attitude towards other religions and cultures were also mentioned in public. There are many reasons for Korean churches to lose trust from people. One of the reasons for that is the quantitative growth of church and expansion of the power of church, which is a direction that has been practised so far as a missionary goal. The zeal for spreading gospel has undermined the trust of church and become a deteriorating factor for mission, which is irony. In such problematic situations, the change of paradigm is required for new mission. The passion for evangelisation should not only focus on the quantitative growth of church; it should change its direction for serving the world in lieu with the plan of God for the activity of redemption on this land. A hint of such mission can be found in ecumenical mission. Ecumenical mission is a new paradigm which was discussed in ecumenical movement led mainly by WCC, and its aim is to participate in activities of redemption of God for life in this world. Christian education has been a tool for the expansion of Christian power in the context of traditional mission. Reflecting on the role of Christian education as such, the change of direction as practical movement for the kingdom of God was tried in ecumenical movement: the beginning of the discussion of Christian education based on ecumenical mission. Due to exclusivity, aggressive mission, and the excessive attention to the system of ecclesiastical authority rather than life, Korean churches, which have lost trust in this society, should recover themselves as the model of the kingdom of God, and the establishment of mission education based on ecumenical mission is required for them to become a community towards life. Furthermore, this is an urgent task for Korean churches to implement such mission education in a church community.

A Study of the Model Christian Familial-Spiritual Education for The Era of Covid-19 (코로나19 시대의 기독교적 가정영성교육 모형: 비블리오드라마를 중심으로)

  • Choi, Eun Taek
    • Journal of Christian Education in Korea
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    • v.63
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    • pp.91-120
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    • 2020
  • This study suggests a spiritual education for the Christian family as a strategy to cope with the risky situation of the Korean Church during the Covid-19 pandemic. Today, we live in a chaotic epoch since the rapid development of the science caused the Fourth Industrial Revolution and the Covid-19 pandemic gave rise to a wide array of changes throughout the society. Korean Church in these circumstances is required to have relevant responses to the kaleidoscopic changes. Especially, not to mention the face-to-face public worship service, in the situation where the congregation members even find it difficult to meet one another in a small group, it becomes a crucial issue how Christians maintain their faith and community in the healthy spirituality. As such, viewing that Christian education within the family will become much more important, this study conducts research for familial-spiritual education. For the research, this paper, first of all, attempts to understand the era of Covid-19. It is to see what the Novel Corona Virus is and what the feature of the epoch of Covid-19 might be. Based upon the understanding, this research discusses what Christian spirituality is asked for and the orientation towards which Christian education should go on. It is particularly to say that a spiritual education for the family becomes integral. The education for the family might be possible through Bibliodrama so that this study establishes a specific model of Christian education employing Bibliodrama. The discussion above shows three academic significances. First, this paper, within the domain of Christian education, suggests an alternative research which is to solve Korean Church's diverse problems caused by Covid-19. Second, this research attempts an analytical understanding of the Covid-19 period within the Christian education area. Finally, when specific and practical research for the field of Christian education during the Covid-19 pandemic is required, this study considers that Christian education within the family is overarching, thus proposing a specific model for familial-spiritual education hiring Bibliodrama.

HPLC-MS/MS Detection and Sonodegradation of Bisphenol A in Water (HPLC-MS/MS를 이용한 Bisphenol A 분석 및 초음파에 의한 분해 특성 조사)

  • Park, Jong-Sung;Yoon, Yeo-Min;Her, Nam-Guk
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.6
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    • pp.639-648
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    • 2010
  • The optimal conditions for the analysis of BPA by HPLC-MS/MS was investigated and the ultrasound degradation capacity of the BPA, with the goal to establish the proper directions for analyzing infinitesimal quantities of BPA by HPLC-MS/MS was examined. The MDL and LOQ of BPA analyzed by HPLC-MS/MS were measured 0.13 nM and 1.3 nM respectively, its sensitivity about 620 and 32 times greater than HPLC-UV (MDL: 81.1 nM, LOQ: 811 nM) and FLD (MDL: 4.6 nM, LOQ: 46 nM). In other words, the new method enables the analysis of BPA with the accuracy up to one 1,180th of the amount specified in U.S. EPA guideline for drinking water. Degradation rate of BPA by ultrasound measured over 95% under 580 kHz and 1000 kHz frequency within 30 minutes of treatment, whereas the rate showed some decrease at 28 kHz frequency. At 580 kHz of ultrasound has proven to be the most effective among others at degradation rate and $k_1$ value, so we concluded that this frequency of ultrasound creates hospitable condition for the combined process of degradation by pyrolysis and oxidization. With the addition of 0.01 mM of $CCl_4$, BPA with the initial concentration of 1 ${\mu}M$ was degraded by more than 98% within 30 minutes, the $k_1$ value measured 5 minutes and 30 minutes into the experiment both showed increases by 1.4 and 1.1 times, respectively, compared with BPA without $CCl_4$. It is also found that the main degradation mechanism of BPA by ultrasound is oxidization process by OH radical, based on the fact that the addition of 10 mM of t-BuOH decreased the rate of BPA degradation by around 60%. However, 33% of BPA degradation rate obtained with the addition of t-BuOH implies further degradation done by pyrolysis or other sorts of radical beside OH radical.

The Role of Home Economics Education in the Fourth Industrial Revolution (4차 산업혁명시대 가정과교육의 역할)

  • Lee, Eun-hee
    • Journal of Korean Home Economics Education Association
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    • v.31 no.4
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    • pp.149-161
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    • 2019
  • At present, we are at the point of change of the 4th industrial revolution era due to the development of artificial intelligence(AI) and rapid technological innovation that no one can predict until now. This study started from the question of 'What role should home economics education play in the era of the Fourth Industrial Revolution?'. The Fourth Industrial Revolution is characterized by AI, cloud computing, Internet of Things(IoT), big data, and Online to Offline(O2O). It will drastically change the social system, science and technology and the structure of the profession. Since the dehumanization of robots and artificial intelligence may occur, the 4th Industrial Revolution Education should be sought to foster future human resources with humanity and citizenship for the future community. In addition, the implication of education in the fourth industrial revolution, which will bring about a change to a super-intelligent and hyper-connected society, is that the role of education should be emphasized so that humans internalize their values as human beings. Character education should be established as a generalized and internalized consciousness with a concept established in the integration of the curriculum, and concrete practical strategies should be prepared. In conclusion, home economics education in the 4th industrial revolution era should play a leading role in the central role of character education, and intrinsic improvement of various human lives. The fourth industrial revolution will change not only what we do, or human mental and physical activities, but also who we are, or human identity. In the information society and digital society, it is important how quickly and accurately it is possible to acquire scattered knowledge. In the information society, it is required to learn how to use knowledge for human beings in rapid change. As such, the fourth industrial revolution seeks to lead the family, organization, and community positively by influencing the systems that shape our lives. Home economics education should take the lead in this role.

Toponymic Practices for Creating and Governing of Cultural Heritage (문화유산 관리를 위한 지명(地名)의 가치와 활용 방안)

  • KIM, Sunbae
    • Korean Journal of Heritage: History & Science
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    • v.54 no.2
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    • pp.56-77
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    • 2021
  • Toponyms are located not only in the site between human cognition and the physical environment but also in the name of cultural heritage. Accordingly, certain identities and ideologies for which human groups and community have sought, their holistic way of life, and all cultural symbols and cosmos, such as sense of place and genius loci, are included in their toponymic heritage. Denoting, symbolizing, integrating and representing the culture and nature belong to the human community. Based on these perceptions of the toponymic heritage, the aims of this article are to examine the values of a toponym as an Intangible Cultural Heritage (ICH) and to suggest the application methods using the toponymic functions for governing of tangible cultural heritage. This article discusses the multivocality, diversity, and non-representational theory of landscape phenomenology intrinsic to the terms of culture and cultural landscape and then the domestic and international issues on the toponymic heritage in the first chapter on the values of toponym as a part of the ICH. In particular, it analyzes the preceding research in the field of toponymy, as well as the Resolutions of UNCSGN and UNGEGN on "Geographical names as culture, heritage and identity" including indigenous, minority and regional language names since 1992, which is related to the UNESCO's Convention for the Safeguarding of the Intangible Cultural Heritage in 2003. Based on this, I suggest that the traits of toponymic cultural heritage and its five standards of selection, i.e., cultural traits of toponyms, historical traits, spatial traits, socio-economic traits and linguistic traits with some examples. In the second chapter discussing on the methods using the toponymic denoting functions for creating and governing of the tangible cultural heritage, it is underlined to maintain the systematic and unified principle regarding the ways of naming in the official cultural heritage and its governing. Lastly, I introduce the possible ways of establishing a conservative area of the historical and cultural environment while using the toponymic scale and multi-toponymic territory. Considering both the spatial and participatory turns in the field of heritage studies in addition to the multiple viewpoints and sense of cultural heritage, I suggest that the conservative area for the cultural heritage and the historical and cultural environment should be set up through choosing the certain toponymic scale and multi-toponymic territory.

On Vortex Reduction Characteristics of Pump Sump Circulating Water Intake Basin of Power Plant Using Hydraulic Experiment (수리실험을 이용한 발전소의 순환수 취수부 흡입수조의 와류저감에 관한 연구)

  • Eom, Junghyun;Lee, Du Han;Kim, Hung Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.6
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    • pp.815-824
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    • 2022
  • Among the main facilities of the power plant, the circulating water used for cooling the power generation system is supplied through the Circulation Water Intake Basin (CWIB). The vortexes of various types generated in the Pump Sump (PS) of CWIB adversely affect the Circulation Water Pump (CWP) and pipelines. In particular, the free surface vortex accompanied by air intake brings about vibration, noise, cavitation etc. and these are the causes of degradation of CWP performance, damage to pipelines. Then power generation is interrupted by the causes. Therefore, it is necessary to investigate the hydraulic characteristics of CWIB through the hydraulic model experiment and apply an appropriate Anti Vortex Device (AVD) that can control the vortex to enable smooth operation of the power plant. In general, free surface vortex is controlled by Curtain Wall (CW) and the submerged vortex is by the anti vortex device of the curtain wall. The detailed specifications are described in the American National Standard for Pump Intake Design. In this study, the circulating water intake part of the Tripoli West 4×350 MW power plant in Libya was targeted, the actual operating conditions were applied, and the vortex reduction effect of the anti vortex device generated in the suction tank among the circulating water intake part was analyzed through a hydraulic model experiment. In addition, a floor splitter was basically applied to control the submerged vortex, and a new type of column curtain wall was additionally applied to control the vortex generated on the free surface to confirm the effect. As a result of analyzing the hydraulic characteristics by additionally applying the newly developed Column Curtain Wall (CCW) to the existing curtain wall, we have found that the vortex was controlled by forming a uniform flow. In addition, the vortex angle generated in the circulating water pump pipeline was 5° or less, which is the design standard of ANSI/HI 9.8, confirming the stability of the flow.

A Study of the Effects of Overseas Direct Investment on Trade in Korea's Manufacturing Industry (한국 제조업 부문 해외직접투자의 수출입유발효과에 관한 연구)

  • Kwon, Pyung-Oh;Lee, Hak-Loh
    • International Commerce and Information Review
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    • v.15 no.3
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    • pp.263-287
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    • 2013
  • This study aims to analyse whether outward foreign direct investment(FDI) by Korean manufacturers has a positive or negative effect on the nation's exports and imports. It provides a comprehensive analysis using both micro and macro approaches to overcome the limitations of the previous studies. In its micro-analysis, this study analyzed the impact of the outstanding outward FDI stock and other related factors on net export/import creation using panel data of 589 overseas affiliates of Korean manufacturers during the period of 2006 to 2011. And in the macro-analysis, the study analyzed the impact of outward FDI on exports using panel data of 23 manufacturing sectors during the period of 2000 to 2011. As a result of empirical study, contrary to the results of most previous studies, Korea's export can be negatively affected when it's manufacturing companies increase their outward FDI and localize their overseas businesses.

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